diff --git a/README.md b/README.md
index 89646ae613..7875a5b096 100755
--- a/README.md
+++ b/README.md
@@ -190,6 +190,7 @@ Other documents:
 
 ## V4 changes
 
+* v4.0, 2021-03-24, RTC: Support WebRTC re-publish stream. 4.0.87
 * v4.0, 2021-03-24, RTC: Use fast parse TWCCID, ignore in packet parsing. 4.0.86
 * v4.0, 2021-03-09, DTLS: Fix ARQ bug, use openssl timeout. 4.0.84
 * v4.0, 2021-03-08, DTLS: Fix dead loop by duplicated Alert message. 4.0.83
diff --git a/trunk/src/app/srs_app_rtc_conn.cpp b/trunk/src/app/srs_app_rtc_conn.cpp
index 5dceaabb8e..e28ab2f427 100644
--- a/trunk/src/app/srs_app_rtc_conn.cpp
+++ b/trunk/src/app/srs_app_rtc_conn.cpp
@@ -466,6 +466,30 @@ srs_error_t SrsRtcPlayStream::initialize(SrsRequest* req, std::map<uint32_t, Srs
     return err;
 }
 
+void SrsRtcPlayStream::on_stream_change(SrsRtcStreamDescription* desc)
+{
+    // Refresh the relation for audio.
+    // TODO: FIMXE: Match by label?
+    if (desc->audio_track_desc_ && audio_tracks_.size() == 1) {
+        uint32_t ssrc = desc->audio_track_desc_->ssrc_;
+        SrsRtcAudioSendTrack* track = audio_tracks_.begin()->second;
+
+        audio_tracks_.clear();
+        audio_tracks_.insert(make_pair(ssrc, track));
+    }
+
+    // Refresh the relation for video.
+    // TODO: FIMXE: Match by label?
+    if (desc->video_track_descs_.size() == 1 && desc->video_track_descs_.size() == 1) {
+        SrsRtcTrackDescription* vdesc = desc->video_track_descs_.at(0);
+        uint32_t ssrc = vdesc->ssrc_;
+        SrsRtcVideoSendTrack* track = video_tracks_.begin()->second;
+
+        video_tracks_.clear();
+        video_tracks_.insert(make_pair(ssrc, track));
+    }
+}
+
 srs_error_t SrsRtcPlayStream::on_reload_vhost_play(string vhost)
 {
     if (req_->vhost != vhost) {
@@ -546,6 +570,9 @@ srs_error_t SrsRtcPlayStream::cycle()
         return srs_error_wrap(err, "create consumer, source=%s", req_->get_stream_url().c_str());
     }
 
+    srs_assert(consumer);
+    consumer->set_handler(this);
+
     // TODO: FIXME: Dumps the SPS/PPS from gop cache, without other frames.
     if ((err = source->consumer_dumps(consumer)) != srs_success) {
         return srs_error_wrap(err, "dumps consumer, url=%s", req_->get_stream_url().c_str());
diff --git a/trunk/src/app/srs_app_rtc_conn.hpp b/trunk/src/app/srs_app_rtc_conn.hpp
index 767d6b0dd3..12187fae2a 100644
--- a/trunk/src/app/srs_app_rtc_conn.hpp
+++ b/trunk/src/app/srs_app_rtc_conn.hpp
@@ -211,7 +211,7 @@ class SrsRtcPLIWorker : virtual public ISrsCoroutineHandler
 
 // A RTC play stream, client pull and play stream from SRS.
 class SrsRtcPlayStream : virtual public ISrsCoroutineHandler, virtual public ISrsReloadHandler
-    , virtual public ISrsHourGlass, virtual public ISrsRtcPLIWorkerHandler
+    , virtual public ISrsHourGlass, virtual public ISrsRtcPLIWorkerHandler, public ISrsRtcStreamChangeCallback
 {
 private:
     SrsContextId cid_;
@@ -235,13 +235,16 @@ class SrsRtcPlayStream : virtual public ISrsCoroutineHandler, virtual public ISr
     bool nack_enabled_;
     bool nack_no_copy_;
 private:
-    // Whether palyer started.
+    // Whether player started.
     bool is_started;
 public:
     SrsRtcPlayStream(SrsRtcConnection* s, const SrsContextId& cid);
     virtual ~SrsRtcPlayStream();
 public:
     srs_error_t initialize(SrsRequest* request, std::map<uint32_t, SrsRtcTrackDescription*> sub_relations);
+// Interface ISrsRtcStreamChangeCallback
+public:
+    void on_stream_change(SrsRtcStreamDescription* desc);
 // interface ISrsReloadHandler
 public:
     virtual srs_error_t on_reload_vhost_play(std::string vhost);
@@ -268,7 +271,7 @@ class SrsRtcPlayStream : virtual public ISrsCoroutineHandler, virtual public ISr
     srs_error_t on_rtcp_ps_feedback(SrsRtcpPsfbCommon* rtcp);
     srs_error_t on_rtcp_rr(SrsRtcpRR* rtcp);
     uint32_t get_video_publish_ssrc(uint32_t play_ssrc);
-// inteface ISrsRtcPLIWorkerHandler
+// Interface ISrsRtcPLIWorkerHandler
 public:
     virtual srs_error_t do_request_keyframe(uint32_t ssrc, SrsContextId cid);
 };
diff --git a/trunk/src/app/srs_app_rtc_source.cpp b/trunk/src/app/srs_app_rtc_source.cpp
index d111d5e577..e9a34533a8 100644
--- a/trunk/src/app/srs_app_rtc_source.cpp
+++ b/trunk/src/app/srs_app_rtc_source.cpp
@@ -152,10 +152,19 @@ SrsNtp SrsNtp::to_time_ms(uint64_t ntp)
     return srs_ntp;
 }
 
+ISrsRtcStreamChangeCallback::ISrsRtcStreamChangeCallback()
+{
+}
+
+ISrsRtcStreamChangeCallback::~ISrsRtcStreamChangeCallback()
+{
+}
+
 SrsRtcConsumer::SrsRtcConsumer(SrsRtcStream* s)
 {
     source = s;
     should_update_source_id = false;
+    handler_ = NULL;
 
     mw_wait = srs_cond_new();
     mw_min_msgs = 0;
@@ -231,6 +240,13 @@ void SrsRtcConsumer::wait(int nb_msgs)
     srs_cond_wait(mw_wait);
 }
 
+void SrsRtcConsumer::on_stream_change(SrsRtcStreamDescription* desc)
+{
+    if (handler_) {
+        handler_->on_stream_change(desc);
+    }
+}
+
 SrsRtcStreamManager::SrsRtcStreamManager()
 {
     lock = NULL;
@@ -354,24 +370,34 @@ void SrsRtcStream::update_auth(SrsRequest* r)
     req->update_auth(r);
 }
 
-srs_error_t SrsRtcStream::on_source_id_changed(SrsContextId id)
+srs_error_t SrsRtcStream::on_source_changed()
 {
     srs_error_t err = srs_success;
 
-    if (!_source_id.compare(id)) {
-        return err;
-    }
+    // Update context id if changed.
+    bool id_changed = false;
+    const SrsContextId& id = _srs_context->get_id();
+    if (_source_id.compare(id)) {
+        id_changed = true;
 
-    if (_pre_source_id.empty()) {
-        _pre_source_id = id;
+        if (_pre_source_id.empty()) {
+            _pre_source_id = id;
+        }
+        _source_id = id;
     }
-    _source_id = id;
 
-    // notice all consumer
+    // Notify all consumers.
     std::vector<SrsRtcConsumer*>::iterator it;
     for (it = consumers.begin(); it != consumers.end(); ++it) {
         SrsRtcConsumer* consumer = *it;
-        consumer->update_source_id();
+
+        // Notify if context id changed.
+        if (id_changed) {
+            consumer->update_source_id();
+        }
+
+        // Notify about stream description.
+        consumer->on_stream_change(stream_desc_);
     }
 
     return err;
@@ -456,9 +482,8 @@ srs_error_t SrsRtcStream::on_publish()
     is_created_ = true;
     is_delivering_packets_ = true;
 
-    // whatever, the publish thread is the source or edge source,
-    // save its id to srouce id.
-    if ((err = on_source_id_changed(_srs_context->get_id())) != srs_success) {
+    // Notify the consumers about stream change event.
+    if ((err = on_source_changed()) != srs_success) {
         return srs_error_wrap(err, "source id change");
     }
 
diff --git a/trunk/src/app/srs_app_rtc_source.hpp b/trunk/src/app/srs_app_rtc_source.hpp
index f22bffc274..1ea9c5a419 100644
--- a/trunk/src/app/srs_app_rtc_source.hpp
+++ b/trunk/src/app/srs_app_rtc_source.hpp
@@ -75,6 +75,17 @@ class SrsNtp
     static uint64_t kMagicNtpFractionalUnit;
 };
 
+// When RTC stream publish and re-publish.
+class ISrsRtcStreamChangeCallback
+{
+public:
+    ISrsRtcStreamChangeCallback();
+    virtual ~ISrsRtcStreamChangeCallback();
+public:
+    virtual void on_stream_change(SrsRtcStreamDescription* desc) = 0;
+};
+
+// The RTC stream consumer, consume packets from RTC stream source.
 class SrsRtcConsumer
 {
 private:
@@ -87,6 +98,9 @@ class SrsRtcConsumer
     srs_cond_t mw_wait;
     bool mw_waiting;
     int mw_min_msgs;
+private:
+    // The callback for stream change event.
+    ISrsRtcStreamChangeCallback* handler_;
 public:
     SrsRtcConsumer(SrsRtcStream* s);
     virtual ~SrsRtcConsumer();
@@ -100,6 +114,9 @@ class SrsRtcConsumer
     virtual srs_error_t dump_packet(SrsRtpPacket2** ppkt);
     // Wait for at-least some messages incoming in queue.
     virtual void wait(int nb_msgs);
+public:
+    void set_handler(ISrsRtcStreamChangeCallback* h) { handler_ = h; } // SrsRtcConsumer::set_handler()
+    void on_stream_change(SrsRtcStreamDescription* desc);
 };
 
 class SrsRtcStreamManager
@@ -154,7 +171,7 @@ class SrsRtcStream
     // For publish, it's the publish client id.
     // For edge, it's the edge ingest id.
     // when source id changed, for example, the edge reconnect,
-    // invoke the on_source_id_changed() to let all clients know.
+    // invoke the on_source_changed() to let all clients know.
     SrsContextId _source_id;
     // previous source id.
     SrsContextId _pre_source_id;
@@ -180,8 +197,10 @@ class SrsRtcStream
     virtual srs_error_t initialize(SrsRequest* r);
     // Update the authentication information in request.
     virtual void update_auth(SrsRequest* r);
-    // The source id changed.
-    virtual srs_error_t on_source_id_changed(SrsContextId id);
+private:
+    // The stream source changed.
+    virtual srs_error_t on_source_changed();
+public:
     // Get current source id.
     virtual SrsContextId source_id();
     virtual SrsContextId pre_source_id();
diff --git a/trunk/src/core/srs_core_version4.hpp b/trunk/src/core/srs_core_version4.hpp
index ef82d18866..2add34d5bd 100644
--- a/trunk/src/core/srs_core_version4.hpp
+++ b/trunk/src/core/srs_core_version4.hpp
@@ -26,6 +26,6 @@
 
 #define VERSION_MAJOR       4
 #define VERSION_MINOR       0
-#define VERSION_REVISION    86
+#define VERSION_REVISION    87
 
 #endif