The electric pump-fed rocket engine is currently a highly promising liquid rocket engine, due to its flexible thrust regulation. This paper established the dynamic equilibrium model of the electric pump-fed rocket engine and studied the influence of motor torque scheme on the thrust regulation time. The thrust regulation characteristics of the electric pump-fed rocket engine under different braking torque and acceleration torque have been analyzed and the following conclusions are drawn: the application of braking torque and acceleration torque successfully reduces the time of thrust reduction process and thrust increase process, respectively. Both of them exist the optimal value to minimize the thrust regulation time. Due to the limitation of the range of motor torque, the electric pump-fed engine has a minimum value of the thrust regulation time and it is more suitable for the multi-stage depth thrust regulation scheme.