It is an effective method to achieve high power,high efficiency fundamental mode laser output that adopting laser diodes double-end-pumped composite crystal configuration.By employing YVO₄-Nd:YVO₄-YVO₄ composite crystal as gain medium and introducing unsymmetrical plane-plane resonator configuration for achieving effective fundamental mode operation,we obtain 34 W CW fundamental mode output power with a pump power of 70 W and an optical-optical conversion efficiency of 48.6%.The laser pulse width reaches 80 ns in acousto optically (AO) Q-switched mode operation,which might be too long for later applications.After shortening the longer arm of resonator,we obtain 30 W CW fundamental mode output power with a pump power of 66 W and an optical-optical conversion efficiency of 45.5%.In the Q-switched mode operation,quasi-CW output with pulse repetition rate from 10 to 200 kHz can be obtained.The relationships of the average power,the pulse width and the peak power versus the pulse repetition rate are investigated in detail.With the pulse repetition rate of 10 kHz,we obtain an average power of 19.3 W with a pulse width of 28 ns,corresponding to a peak power of 68.9 kW.With pulse repetition rate between 100 and 200 kHz,the average power holds at about 27 W and pulse width about 50 ns.Additionally,the analysis on the resonator design and experiment results shows that further optimization for achieving much shorter pulse width and higher peak power is possible.