diff --git a/fastdeploy/cache_manager/transfer_factory/kvcache_transfer/src/kvcache_rdma.cpp b/fastdeploy/cache_manager/transfer_factory/kvcache_transfer/src/kvcache_rdma.cpp
index ae3809add65..60cfff031ab 100644
--- a/fastdeploy/cache_manager/transfer_factory/kvcache_transfer/src/kvcache_rdma.cpp
+++ b/fastdeploy/cache_manager/transfer_factory/kvcache_transfer/src/kvcache_rdma.cpp
@@ -1513,8 +1513,9 @@ bool RDMACommunicator::post_send_with_retry(struct RdmaContext* ctx,
     last_wr->send_flags |= IBV_SEND_SIGNALED;
   }
 
+  struct ibv_send_wr* cur_wr = wr_list;
   do {
-    ret = ibv_post_send(ctx->qp, wr_list, &bad_wr);
+    ret = ibv_post_send(ctx->qp, cur_wr, &bad_wr);
     if (ret == 0) {
       if (need_poll) {
         ctx->conn.wc_count = 0;
@@ -1532,8 +1533,22 @@ bool RDMACommunicator::post_send_with_retry(struct RdmaContext* ctx,
           errno,
           retries + 1,
           max_retries);
+      // Non-blocking CQ drain to free SQ slots before retrying.
+      // Do not use poll_cq_with_timeout here: ibv_post_send failure does not
+      // guarantee a CQE is available (e.g. sync errors, unsignaled WRs), so a
+      // blocking wait would stall the retry loop for up to
+      // RDMA_POLL_CQE_TIMEOUT per attempt (up to 210s total).
+      {
+        struct ibv_wc wc_array[32];
+        int n;
+        while ((n = ibv_poll_cq(ctx->cq, 32, wc_array)) > 0) {
+        }
+      }
       usleep(1000);
       retries++;
+      if (bad_wr)
+        cur_wr =
+            bad_wr;  // resume from the failed WR instead of retrying from head
     }
   } while (retries < max_retries);