This paper reports results of study on self-Q-switched Cr4+ , Nd3+: YAG microchip lasers at 1.064 μm using a quasi-monolithic setup. Pulses with 6 to 60 ns wide (FWHM) and TEM00 mode produced under cw pumping with repetition rates ranging from 1.5 kHz to 23 kHz. Pulsed pumping yielded output pulses with repetition rates from 1 Hz to several kHz and excellent pulse stability. A pulsed pumped microchip oscillator and flash lamp pumped amplifiers were used to set up a MOPA(Master Oscillator and Power Amplifier)system generating 225 kW pulses with 8 ns width.