diff --git a/node-agent/WxAgent.Service/RemoteAgentHostedService.cs b/node-agent/WxAgent.Service/RemoteAgentHostedService.cs
index 333f46c..21e4613 100644
--- a/node-agent/WxAgent.Service/RemoteAgentHostedService.cs
+++ b/node-agent/WxAgent.Service/RemoteAgentHostedService.cs
@@ -192,14 +192,36 @@ public sealed class RemoteAgentHostedService(
                 continue;
 
             var sequence = sourceChanged ? 1 : checkpoint.ConfirmedSequence + 1;
-            var batch = new RemoteSyncBatch(
-                remote.NodeId!, account.AccountId, Guid.NewGuid().ToString("N"), collection.SourceGeneration,
-                "messages", sequence, SerializeCursors(cursorStart), SerializeCursors(collection.NextCursors),
-                string.Empty, collection.IsComplete ? "complete" : "partial", collection.Conversations, collection.Messages);
-            batch = batch with { PayloadHash = RemoteDataBatchAuthorization.ComputePayloadHash(batch) };
-            var queued = queue.Enqueue(reporting, batch);
-            if (queued.Accepted && queued.Batch is not null)
-                state.MarkCollected(queued.Batch, collection.UnavailableSources);
+            var remainingConversations = collection.Conversations.ToList();
+            var remainingMessages = collection.Messages.ToList();
+            var cursorStartJson = SerializeCursors(cursorStart);
+            var cursorEndJson = SerializeCursors(collection.NextCursors);
+            var allQueued = true;
+            RemoteSyncBatch? lastQueuedBatch = null;
+            while (remainingConversations.Count > 0 || remainingMessages.Count > 0 || lastQueuedBatch is null)
+            {
+                var conversationCount = Math.Min(remainingConversations.Count, RemoteDataProtocol.MaxBatchMessages);
+                var conversations = remainingConversations.Take(conversationCount).ToArray();
+                remainingConversations.RemoveRange(0, conversationCount);
+                var messageCount = Math.Min(remainingMessages.Count, RemoteDataProtocol.MaxBatchMessages - conversations.Length);
+                var messages = remainingMessages.Take(messageCount).ToArray();
+                remainingMessages.RemoveRange(0, messageCount);
+                var batch = new RemoteSyncBatch(
+                    remote.NodeId!, account.AccountId, Guid.NewGuid().ToString("N"), collection.SourceGeneration,
+                    "messages", sequence++, cursorStartJson, cursorEndJson, string.Empty,
+                    collection.IsComplete ? "complete" : "partial", conversations, messages);
+                batch = batch with { PayloadHash = RemoteDataBatchAuthorization.ComputePayloadHash(batch) };
+                var queued = queue.Enqueue(reporting, batch);
+                if (!queued.Accepted || queued.Batch is null)
+                {
+                    allQueued = false;
+                    break;
+                }
+                lastQueuedBatch = queued.Batch;
+                cursorStartJson = cursorEndJson;
+            }
+            if (allQueued && lastQueuedBatch is not null)
+                state.MarkCollected(lastQueuedBatch, collection.UnavailableSources);
             if (!collection.IsComplete)
                 logger.LogWarning("Data sync is partial; accountId={AccountId}; unavailableSources={UnavailableSourceCount}.", account.AccountId, collection.UnavailableSources.Count);
         }