diff --git a/tools/releasetools/add_img_to_target_files.py b/tools/releasetools/add_img_to_target_files.py
index e9419fe..b566e1d 100755
--- a/tools/releasetools/add_img_to_target_files.py
+++ b/tools/releasetools/add_img_to_target_files.py
@@ -72,7 +72,7 @@
 OPTIONS.replace_verity_private_key = False
 OPTIONS.is_signing = False
 
-# Partitions that should have their care_map added to META/care_map.txt.
+# Partitions that should have their care_map added to META/care_map.pb
 PARTITIONS_WITH_CARE_MAP = ('system', 'vendor', 'product', 'product_services',
                             'odm')
 # Use a fixed timestamp (01/01/2009 00:00:00 UTC) for files when packaging
@@ -556,12 +556,12 @@
     assert available, "Failed to find " + img_name
 
 
-def AddCareMapTxtForAbOta(output_zip, ab_partitions, image_paths):
-  """Generates and adds care_map.txt for system and vendor partitions.
+def AddCareMapForAbOta(output_zip, ab_partitions, image_paths):
+  """Generates and adds care_map.pb for system and vendor partitions.
 
   Args:
     output_zip: The output zip file (needs to be already open), or None to
-        write care_map.txt to OPTIONS.input_tmp/.
+        write care_map.pb to OPTIONS.input_tmp/.
     ab_partitions: The list of A/B partitions.
     image_paths: A map from the partition name to the image path.
   """
@@ -594,11 +594,11 @@
   p = common.Run(care_map_gen_cmd, stdout=subprocess.PIPE,
                  stderr=subprocess.STDOUT)
   output, _ = p.communicate()
-  assert p.returncode == 0, "Failed to generate the care_map proto message."
+  assert p.returncode == 0, "Failed to generate the care_map.pb message."
   if OPTIONS.verbose:
     print(output.rstrip())
 
-  care_map_path = "META/care_map.txt"
+  care_map_path = "META/care_map.pb"
   if output_zip and care_map_path not in output_zip.namelist():
     common.ZipWrite(output_zip, temp_care_map, arcname=care_map_path)
   else:
@@ -658,7 +658,7 @@
 def ReplaceUpdatedFiles(zip_filename, files_list):
   """Updates all the ZIP entries listed in files_list.
 
-  For now the list includes META/care_map.txt, and the related files under
+  For now the list includes META/care_map.pb, and the related files under
   SYSTEM/ after rebuilding recovery.
   """
   common.ZipDelete(zip_filename, files_list)
@@ -863,9 +863,9 @@
     # ready under IMAGES/ or RADIO/.
     CheckAbOtaImages(output_zip, ab_partitions)
 
-    # Generate care_map.txt for system and vendor partitions (if present), then
-    # write this file to target_files package.
-    AddCareMapTxtForAbOta(output_zip, ab_partitions, partitions)
+    # Generate care_map.pb for system and vendor partitions (if present),
+    # then write this file to target_files package.
+    AddCareMapForAbOta(output_zip, ab_partitions, partitions)
 
   # Radio images that need to be packed into IMAGES/, and product-img.zip.
   pack_radioimages_txt = os.path.join(
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index eaba4df..e75adf5 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -1167,7 +1167,8 @@
         'payload_properties.txt',
     )
     self.optional = (
-        # care_map.txt is available only if dm-verity is enabled.
+        # care_map is available only if dm-verity is enabled.
+        'care_map.pb',
         'care_map.txt',
         # compatibility.zip is available only if target supports Treble.
         'compatibility.zip',
@@ -1786,13 +1787,16 @@
   target_zip = zipfile.ZipFile(target_file, "r")
   if (target_info.get("verity") == "true" or
       target_info.get("avb_enable") == "true"):
-    care_map_path = "META/care_map.txt"
-    namelist = target_zip.namelist()
-    if care_map_path in namelist:
-      care_map_data = target_zip.read(care_map_path)
-      # In order to support streaming, care_map.txt needs to be packed as
+    care_map_list = [x for x in ["care_map.pb", "care_map.txt"] if
+                     "META/" + x in target_zip.namelist()]
+
+    # Adds care_map if either the protobuf format or the plain text one exists.
+    if care_map_list:
+      care_map_name = care_map_list[0]
+      care_map_data = target_zip.read("META/" + care_map_name)
+      # In order to support streaming, care_map needs to be packed as
       # ZIP_STORED.
-      common.ZipWriteStr(output_zip, "care_map.txt", care_map_data,
+      common.ZipWriteStr(output_zip, care_map_name, care_map_data,
                          compress_type=zipfile.ZIP_STORED)
     else:
       print("Warning: cannot find care map file in target_file package")
diff --git a/tools/releasetools/sign_target_files_apks.py b/tools/releasetools/sign_target_files_apks.py
index cb0c268..db006d1 100755
--- a/tools/releasetools/sign_target_files_apks.py
+++ b/tools/releasetools/sign_target_files_apks.py
@@ -395,7 +395,7 @@
       pass
 
     # Skip the care_map as we will regenerate the system/vendor images.
-    elif filename == "META/care_map.txt":
+    elif filename == "META/care_map.pb" or filename == "META/care_map.txt":
       pass
 
     # A non-APK file; copy it verbatim.
diff --git a/tools/releasetools/test_add_img_to_target_files.py b/tools/releasetools/test_add_img_to_target_files.py
index 834e989..c60b496 100644
--- a/tools/releasetools/test_add_img_to_target_files.py
+++ b/tools/releasetools/test_add_img_to_target_files.py
@@ -23,7 +23,7 @@
 import common
 import test_utils
 from add_img_to_target_files import (
-    AddCareMapTxtForAbOta, AddPackRadioImages, AppendVBMetaArgsForPartition,
+    AddCareMapForAbOta, AddPackRadioImages, AppendVBMetaArgsForPartition,
     CheckAbOtaImages, GetCareMap)
 from rangelib import RangeSet
 
@@ -40,7 +40,7 @@
     common.Cleanup()
 
   def _verifyCareMap(self, expected, file_name):
-    """Parses the care_map proto; and checks the content in plain text."""
+    """Parses the care_map.pb; and checks the content in plain text."""
     text_file = common.MakeTempFile(prefix="caremap-", suffix=".txt")
 
     # Calls an external binary to convert the proto message.
@@ -139,8 +139,8 @@
                       images + ['baz'])
 
   @staticmethod
-  def _test_AddCareMapTxtForAbOta():
-    """Helper function to set up the test for test_AddCareMapTxtForAbOta()."""
+  def _test_AddCareMapForAbOta():
+    """Helper function to set up the test for test_AddCareMapForAbOta()."""
     OPTIONS.info_dict = {
         'system_verity_block_device' : '/dev/block/system',
         'vendor_verity_block_device' : '/dev/block/vendor',
@@ -164,71 +164,71 @@
     }
     return image_paths
 
-  def test_AddCareMapTxtForAbOta(self):
-    image_paths = self._test_AddCareMapTxtForAbOta()
+  def test_AddCareMapForAbOta(self):
+    image_paths = self._test_AddCareMapForAbOta()
 
-    AddCareMapTxtForAbOta(None, ['system', 'vendor'], image_paths)
+    AddCareMapForAbOta(None, ['system', 'vendor'], image_paths)
 
-    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.txt')
+    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.pb')
     expected = ['system', RangeSet("0-5 10-15").to_string_raw(), 'vendor',
                 RangeSet("0-9").to_string_raw()]
 
     self._verifyCareMap(expected, care_map_file)
 
-  def test_AddCareMapTxtForAbOta_withNonCareMapPartitions(self):
+  def test_AddCareMapForAbOta_withNonCareMapPartitions(self):
     """Partitions without care_map should be ignored."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+    image_paths = self._test_AddCareMapForAbOta()
 
-    AddCareMapTxtForAbOta(
+    AddCareMapForAbOta(
         None, ['boot', 'system', 'vendor', 'vbmeta'], image_paths)
 
-    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.txt')
+    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.pb')
     expected = ['system', RangeSet("0-5 10-15").to_string_raw(), 'vendor',
                 RangeSet("0-9").to_string_raw()]
 
     self._verifyCareMap(expected, care_map_file)
 
-  def test_AddCareMapTxtForAbOta_withAvb(self):
+  def test_AddCareMapForAbOta_withAvb(self):
     """Tests the case for device using AVB."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+    image_paths = self._test_AddCareMapForAbOta()
     OPTIONS.info_dict = {
         'avb_system_hashtree_enable' : 'true',
         'avb_vendor_hashtree_enable' : 'true',
     }
 
-    AddCareMapTxtForAbOta(None, ['system', 'vendor'], image_paths)
+    AddCareMapForAbOta(None, ['system', 'vendor'], image_paths)
 
-    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.txt')
+    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.pb')
     expected = ['system', RangeSet("0-5 10-15").to_string_raw(), 'vendor',
                 RangeSet("0-9").to_string_raw()]
 
     self._verifyCareMap(expected, care_map_file)
 
-  def test_AddCareMapTxtForAbOta_verityNotEnabled(self):
-    """No care_map.txt should be generated if verity not enabled."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+  def test_AddCareMapForAbOta_verityNotEnabled(self):
+    """No care_map.pb should be generated if verity not enabled."""
+    image_paths = self._test_AddCareMapForAbOta()
     OPTIONS.info_dict = {}
-    AddCareMapTxtForAbOta(None, ['system', 'vendor'], image_paths)
+    AddCareMapForAbOta(None, ['system', 'vendor'], image_paths)
 
-    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.txt')
+    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.pb')
     self.assertFalse(os.path.exists(care_map_file))
 
-  def test_AddCareMapTxtForAbOta_missingImageFile(self):
+  def test_AddCareMapForAbOta_missingImageFile(self):
     """Missing image file should be considered fatal."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+    image_paths = self._test_AddCareMapForAbOta()
     image_paths['vendor'] = ''
-    self.assertRaises(AssertionError, AddCareMapTxtForAbOta, None,
+    self.assertRaises(AssertionError, AddCareMapForAbOta, None,
                       ['system', 'vendor'], image_paths)
 
-  def test_AddCareMapTxtForAbOta_zipOutput(self):
+  def test_AddCareMapForAbOta_zipOutput(self):
     """Tests the case with ZIP output."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+    image_paths = self._test_AddCareMapForAbOta()
 
     output_file = common.MakeTempFile(suffix='.zip')
     with zipfile.ZipFile(output_file, 'w') as output_zip:
-      AddCareMapTxtForAbOta(output_zip, ['system', 'vendor'], image_paths)
+      AddCareMapForAbOta(output_zip, ['system', 'vendor'], image_paths)
 
-    care_map_name = "META/care_map.txt"
+    care_map_name = "META/care_map.pb"
     temp_dir = common.MakeTempDir()
     with zipfile.ZipFile(output_file, 'r') as verify_zip:
       self.assertTrue(care_map_name in verify_zip.namelist())
@@ -238,27 +238,28 @@
                 RangeSet("0-9").to_string_raw()]
     self._verifyCareMap(expected, os.path.join(temp_dir, care_map_name))
 
-  def test_AddCareMapTxtForAbOta_zipOutput_careMapEntryExists(self):
+  def test_AddCareMapForAbOta_zipOutput_careMapEntryExists(self):
     """Tests the case with ZIP output which already has care_map entry."""
-    image_paths = self._test_AddCareMapTxtForAbOta()
+    image_paths = self._test_AddCareMapForAbOta()
 
     output_file = common.MakeTempFile(suffix='.zip')
     with zipfile.ZipFile(output_file, 'w') as output_zip:
-      # Create an existing META/care_map.txt entry.
-      common.ZipWriteStr(output_zip, 'META/care_map.txt', 'dummy care_map.txt')
+      # Create an existing META/care_map.pb entry.
+      common.ZipWriteStr(output_zip, 'META/care_map.pb',
+                         'dummy care_map.pb')
 
-      # Request to add META/care_map.txt again.
-      AddCareMapTxtForAbOta(output_zip, ['system', 'vendor'], image_paths)
+      # Request to add META/care_map.pb again.
+      AddCareMapForAbOta(output_zip, ['system', 'vendor'], image_paths)
 
     # The one under OPTIONS.input_tmp must have been replaced.
-    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.txt')
+    care_map_file = os.path.join(OPTIONS.input_tmp, 'META', 'care_map.pb')
     expected = ['system', RangeSet("0-5 10-15").to_string_raw(), 'vendor',
                 RangeSet("0-9").to_string_raw()]
 
     self._verifyCareMap(expected, care_map_file)
 
     # The existing entry should be scheduled to be replaced.
-    self.assertIn('META/care_map.txt', OPTIONS.replace_updated_files_list)
+    self.assertIn('META/care_map.pb', OPTIONS.replace_updated_files_list)
 
   def test_AppendVBMetaArgsForPartition(self):
     OPTIONS.info_dict = {}
diff --git a/tools/releasetools/test_ota_from_target_files.py b/tools/releasetools/test_ota_from_target_files.py
index 8416af7..1d8a786 100644
--- a/tools/releasetools/test_ota_from_target_files.py
+++ b/tools/releasetools/test_ota_from_target_files.py
@@ -889,6 +889,7 @@
         property_files.required)
     self.assertEqual(
         (
+            'care_map.pb',
             'care_map.txt',
             'compatibility.zip',
         ),
@@ -984,6 +985,7 @@
         property_files.required)
     self.assertEqual(
         (
+            'care_map.pb',
             'care_map.txt',
             'compatibility.zip',
         ),