diff --git a/tools/doxygen/Doxyfile.c++ b/tools/doxygen/Doxyfile.c++
index 1d2aa959557..c8c7183eaeb 100644
--- a/tools/doxygen/Doxyfile.c++
+++ b/tools/doxygen/Doxyfile.c++
@@ -792,6 +792,7 @@ doc/service_config.md \
 doc/status_ordering.md \
 doc/statuscodes.md \
 doc/stress_test_framework.md \
+doc/unit_testing.md \
 doc/wait-for-ready.md \
 include/grpc++/alarm.h \
 include/grpc++/channel.h \
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index 9664234f9f4..183f660bb5c 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -792,6 +792,7 @@ doc/service_config.md \
 doc/status_ordering.md \
 doc/statuscodes.md \
 doc/stress_test_framework.md \
+doc/unit_testing.md \
 doc/wait-for-ready.md \
 include/grpc++/alarm.h \
 include/grpc++/channel.h \
diff --git a/tools/doxygen/Doxyfile.core b/tools/doxygen/Doxyfile.core
index c3bfc6c4a8e..2a076fce823 100644
--- a/tools/doxygen/Doxyfile.core
+++ b/tools/doxygen/Doxyfile.core
@@ -792,6 +792,7 @@ doc/service_config.md \
 doc/status_ordering.md \
 doc/statuscodes.md \
 doc/stress_test_framework.md \
+doc/unit_testing.md \
 doc/wait-for-ready.md \
 include/grpc/byte_buffer.h \
 include/grpc/byte_buffer_reader.h \
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index 51d77c2b521..7b7a406e117 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -792,6 +792,7 @@ doc/service_config.md \
 doc/status_ordering.md \
 doc/statuscodes.md \
 doc/stress_test_framework.md \
+doc/unit_testing.md \
 doc/wait-for-ready.md \
 include/grpc/byte_buffer.h \
 include/grpc/byte_buffer_reader.h \