By using symmetried splitstep Fourier method(SSFM) for solving the nonlinear Schrdinger equation(NLS),the characteristics of phasesensitive soliton switching in optical fiber couplers have been studied.Transmission behaviors of the main pulse will be dramatically controlled by the initial phase of a relative weak soliton in another fiber core. Different switching properties will be obtained,provided the initial solitons phases into two fiber cores are selected appropriately.