diff --git a/configure.ac b/configure.ac
index aa424d534..90399c159 100644
--- a/configure.ac
+++ b/configure.ac
@@ -404,6 +404,9 @@ dnl       fi
    *linux*)
      TARGET_OS=linux
      ;;
+   *freebsd*)
+     LEVELDB_TARGET_FLAGS="-DOS_FREEBSD"
+     ;;
    *)
      ;;
 esac