In order to study the interaction between light and target at long distance,a design solution of a Q-switched laser diode and flash-lamp pumped Nd∶YVO4+Nd∶YAG oscillator/amplifier laser was presented.This laser can produce 100W average output power with a repetition rate of 1 kHz and a pulse width less than 20ns.The solution and the parameters of this laser were analyzed and calculated.The experimental results indicate the laser has the characteristics of low cost and the miniaturization,which meets the requirement of practical applications.