diff --git a/tests/internal/fuzzers/cmetrics_decode_fuzz.c b/tests/internal/fuzzers/cmetrics_decode_fuzz.c
index 1d1098c0f19..707f0e6ee4b 100644
--- a/tests/internal/fuzzers/cmetrics_decode_fuzz.c
+++ b/tests/internal/fuzzers/cmetrics_decode_fuzz.c
@@ -17,6 +17,7 @@
  *  limitations under the License.
  */
 
+#include <cmetrics/cmt_decode_msgpack.h>
 #include <cmetrics/cmt_decode_opentelemetry.h>
 #include <cmetrics/cmt_decode_prometheus.h>