Voice gateway online monitoring method

The invention relates to the technology of a voice over internet phone (VOIP) system and provides a voice gateway online monitoring method which solves the problem that instantaneity of an achieved monitoring function on an existing VOIP voice gateway can not be guaranteed. The technical schemes includes: negotiating an encode mode used by call into a G711A rule through a system, redirecting two routers of RTP streams of the call into an interior buffer queue, and respectively decoding two routers of real-time transport protocol RTP streams in the interior buffer queue into pulse code modulation PCM data, then utilizing software to combine the two routers of PCM data into one router of PCM data through sound mixing, then converting the combined PCM data into G711A-rule coded format data, finally, sending the converted G711A-rule coded format data to a monitoring party through RTP data messages. The voice gateway online monitoring method has the advantages of achieving real-time monitoring and being suitable for a VOIP voice gate way monitoring system.