Mode locked and cavity dumping techniques are comtined to get picosecond pulse with high energy at high repetition rate. The mechanism and physical image of cavity-dumping mode-locked laser are analyzed and factors which affect the dumping efficiency of cavity-dumping laser are studied. Cavity-dumping mode-locked laser at repetition rate of 10 kHz can be realized with the help of NdYVO4 SESAM mode-locking and a BBO modulator placed in cavity. When pump power is 14.1 W, pulses with energy of 6.5 μJ are obtained, and the pulse width is about 10.4 ps. This kind of laser will have good prospects for development because high energy pulses can be obtained directly from mode-locked oscillator.