Nd∶YAP laser crystal with good polarization property is pumped by pulse laser diode array.An electro-optical crystal LiNbO3 and flat-flat cavity are used as polarizer and replace the Grand-Foucault prism at the same time.The 1341 nm laser pulses with 70 ns pulse width and 1.02 mJ energy are obtained under the condition that the delay time is 150 μs and pumping power is 4 times more than threshold gain.Experiments show that the Nd∶YAP crystal in place of Grand-Foucault prism as the polarizer of the electro-optic Q-switch can get better Q-switch effect.Compared with the theoretical calculation,the energy decreases by 18% and pulse width increases by 44 ns.When inserting Grand-Foucault prism,the energy is reduced by 25% and pulse width increased by 28%.This Q-switch method can reduce the cavity loss and shorten the pulse width.It is helpful for the design of new high-power pulsed laser.