diff --git a/webrtc/RtpExt.cpp b/webrtc/RtpExt.cpp
index bf749fa9..7679abc7 100644
--- a/webrtc/RtpExt.cpp
+++ b/webrtc/RtpExt.cpp
@@ -579,6 +579,10 @@ string RtpExtContext::getRid(uint32_t ssrc) const{
     return it->second;
 }
 
+void RtpExtContext::setRid(uint32_t ssrc, const string &rid) {
+    _ssrc_to_rid[ssrc] = rid;
+}
+
 void RtpExtContext::changeRtpExtId(const RtpHeader *header, bool is_recv, string *rid_ptr) {
     string rid, repaired_rid;
     auto ext_map = RtpExt::getExtValue(header);
diff --git a/webrtc/RtpExt.h b/webrtc/RtpExt.h
index d7a90386..3671bc90 100644
--- a/webrtc/RtpExt.h
+++ b/webrtc/RtpExt.h
@@ -119,6 +119,7 @@ public:
 
     void setOnGetRtp(OnGetRtp cb);
     string getRid(uint32_t ssrc) const;
+    void setRid(uint32_t ssrc, const string &rid);
     void changeRtpExtId(const RtpHeader *header, bool is_recv, string *rid_ptr = nullptr);
 
 private:
diff --git a/webrtc/WebRtcTransport.cpp b/webrtc/WebRtcTransport.cpp
index 501e69d9..2eb7cb1f 100644
--- a/webrtc/WebRtcTransport.cpp
+++ b/webrtc/WebRtcTransport.cpp
@@ -432,6 +432,17 @@ void WebRtcTransportImp::onStartWebRTC() {
                 _ssrc_to_track[ssrc] = track;
                 InfoL << "get rtp, pt:" << (int) pt << ", ssrc:" << ssrc << ", rid:" << rid;
             });
+
+            int index = 0;
+            for (auto &ssrc : m_offer->rtp_ssrc_sim) {
+                //记录ssrc对应的MediaTrack
+                _ssrc_to_track[ssrc.ssrc] = track;
+                if (m_offer->rtp_rids.size() > index) {
+                    //支持firefox的simulcast, 提前映射好ssrc和rid的关系
+                    track->rtp_ext_ctx->setRid(ssrc.ssrc, m_offer->rtp_rids[index]);
+                }
+                ++index;
+            }
         }
     }