diff --git a/tools/releasetools/merge_target_files.py b/tools/releasetools/merge_target_files.py
index ba9e740..b1b4a16 100755
--- a/tools/releasetools/merge_target_files.py
+++ b/tools/releasetools/merge_target_files.py
@@ -456,6 +456,12 @@
     # false in the partial builds to prevent duplicate building of super.img.
     merged_dict['build_super_partition'] = 'true'
 
+  # If AVB is enabled then ensure that we build vbmeta.img.
+  # Partial builds with AVB enabled may set PRODUCT_BUILD_VBMETA_IMAGE=false to
+  # skip building an incomplete vbmeta.img.
+  if merged_dict.get('avb_enable') == 'true':
+    merged_dict['avb_building_vbmeta_image'] = 'true'
+
   # Replace <image>_selinux_fc values with framework or vendor file_contexts.bin
   # depending on which dictionary the key came from.
   # Only the file basename is required because all selinux_fc properties are