diff --git a/src/fdb_kvdb.c b/src/fdb_kvdb.c
index 123ab3e..0f48395 100644
--- a/src/fdb_kvdb.c
+++ b/src/fdb_kvdb.c
@@ -1754,6 +1754,9 @@ fdb_err_t fdb_kvdb_init(fdb_kvdb_t db, const char *name, const char *path, struc
     /* must be aligned with write granularity */
     FDB_ASSERT((FDB_STR_KV_VALUE_MAX_SIZE * 8) % FDB_WRITE_GRAN == 0);
 
+    /* lock the KVDB */
+    db_lock(db);
+
     result = _fdb_init_ex((fdb_db_t) db, name, path, FDB_DB_TYPE_KV, user_data);
     if (result != FDB_NO_ERR) {
         goto __exit;
@@ -1806,6 +1809,9 @@ __exit:
 
     _fdb_init_finish((fdb_db_t)db, result);
 
+    /* unlock the KVDB */
+    db_unlock(db);
+
     return result;
 }
 
diff --git a/src/fdb_tsdb.c b/src/fdb_tsdb.c
index e6c5dd6..ffe3cbb 100644
--- a/src/fdb_tsdb.c
+++ b/src/fdb_tsdb.c
@@ -927,6 +927,9 @@ fdb_err_t fdb_tsdb_init(fdb_tsdb_t db, const char *name, const char *path, fdb_g
 
     FDB_ASSERT(get_time);
 
+    /* lock the TSDB */
+    db_lock(db);
+
     result = _fdb_init_ex((fdb_db_t)db, name, path, FDB_DB_TYPE_TS, user_data);
     if (result != FDB_NO_ERR) {
         goto __exit;
@@ -996,6 +999,9 @@ __exit:
 
     _fdb_init_finish((fdb_db_t)db, result);
 
+    /* unlock the TSDB */
+    db_unlock(db);
+
     return result;
 }