The invention discloses a process layer tri-play message transport real-time scheduling method. The method includes the steps: slaves transmit time merging requests containing message feature information to a master; the master generates a message transport time node table according to the message transport feature data transmitted by all slaves, enters a mode of merging ready, and informs the slaves of time merging update information; the slaves update their message transport time node tables according to the time merging update information transmitted by the master; the master and the slaves both control message transport according to the same message transport time node tables. According to the method, the master is used to collect and analyze message transport feature data of all slaves in a network, message transport scheduling information, the message transport time node table, of the whole network is generated, the problem of possible message transport conflicts is prevented accordingly, and network delay stability, SV message uniformity and GOOSE message real-time transport are maximally increased.