diff --git a/rocksdb/db.pxd b/rocksdb/db.pxd
index a077dbd..a609d1c 100644
--- a/rocksdb/db.pxd
+++ b/rocksdb/db.pxd
@@ -26,7 +26,7 @@ cdef extern from "rocksdb/db.h" namespace "rocksdb":
     cdef struct LiveFileMetaData:
         string name
         int level
-        size_t size
+        uint64_t size
         string smallestkey
         string largestkey
         SequenceNumber smallest_seqno