Abstract: Using the Cr4+:Nd3＋:YAG microchip pumped by LD, the self Qswitched laser pulses with the repetition rate of 2.78kHz and pulse width of 6ns are obtained in the CW case. Through the pre-pumping with the pulsed modulated current the self Qswitched output laser with a controllable repetition rate is realized. Compare with the extra-cavity selfQswitched microchip laser the monolithic microchip laser possess higher transform efficiency, more narrow pulse width and high repetition rate. Also such a laser constructed compact and easy to be adjusted．