The paper proposed a design scheme of emergency communication security system of coal mine. The system's core namely emergency rescue software platform integrates underground broadcast telephone, PHS, WiFi mobile phone, dispatching telephone, underground broadcasting system through relay gateway and special converter, so as to realize interconnection among communication systems. And the system can realize interconnection with personnel location system of mine and integrated access with industrial Ethernet of mine through emergency rescue software platform. The actual test result showed that the system has functions of line management, audio playing, push-to-talk, broadcasting and emergency communication rescue, which improves efficiency of emergency rescue work.