Abstract: In the process of testing, simulating and verifying the avionics system, the problem that different transmission tasks which consist of diverse data and words cause time collisions on the time axis may happen when an ARINC429 bus is used to carry out the periodic and time transmission tasks of multiple Labels. Firstly, in this paper, a research concerning the time interval of the time collisions which might be caused among the task signals transmitted on an ARINC429 bus was conducted. Secondly, a task planning method based on the least common multiple period and the time slice with the greatest common divisor was proposed. Lastly, by carrying out the planning of the task signals to be transmitted on an ARINC429 bus, the single-bus collisions in the transmission of multiple tasks on an ARINC429 bus were solved and the utilization rate of the bus was improved at the same time.