The invention discloses a real-time control method for asynchronous messages of a 1553B bus. An IP core (intellectual property core) of hardware is used for realizing transmission control over the asynchronous messages of the 1553B bus, including transmission of non-periodic messages and zero clearing of a service request bit and a vector character of each RT (remote terminal), and the real-time response to a service request of each RT and timely zero clearing of a status bit and the vector character of each RT are ensured. Compared with a method for realizing asynchronous communication through an upper computer, the real-time control method has the advantages that the transmission of the non-periodic messages is realized through condition messages of a BC (bus controller), the condition messages are only executed in a very short time, the real-time transmission of the non-periodic messages can be realized, and the transmission time sequence of the non-periodic messages on the bus can be ensured. The service request bit of a status word and the vector character are realized through a hardware zero-clearing function of each RT, the real-time property is good, the service request bit and the vector character can be timely cleared, and repeated processing of the same service request of each RT is avoided. According to the control method, the whole process is controlled in the hardware, and the architecture design of a system can be simplified.