In accelerator-driven subcritical system(ADS),the transient characteristic is quite different from that of traditional critical system due to its strong external neutron source and its fuel composition for transmutation.This paper presents a coupled stochastic-deterministic method for analysing the transient characteristic of ADS.After comparing various reactor transient calculation methods,predictor-corrector improved quasi-static method was chosen to handle the time variable of neutron spacetime kinetics ...