Abstract: The characteristic of the transmitting delay of forward and feedback channels were analyzed. According to theworkingmodes of actuators, a linear control object is converted into time-driven and event- driven discrete time models. Two control methods for field bus control system were proposed. The first method transforms randomdelay into constant delay that is then compensated; the sencond method processes random delay directly. These two methods compensate each other and can eliminate the deterioration of delay to the control system performances of field buses.