A kind of vertical-cavity surface-emitter laser (VCSEL) side-pumped all solid-state laser is studied. A compact and stable Nd∶YAG solid-state laser is reported. The laser is side-pumped by VCSEL arrays, and the VCSEL arrays are collimated by microlens array. A cylindrical lens is used to reshape the pump beam into a linear beam to achieve high power density. Besides, the Cr4+∶YAG crystal is used as saturable absorber to be the passive Q-switch. The laser output with 40 Hz repetition frequency, 4 ns pulse width and single pulse energy of 2.1 mJ is obtained. The experimental results show that the laser can achieve stable laser output in a large temperature range. The laser has a compact structure and high resistance to detuning and vibration. It can be used as a light source for future space laser detection and other special environments.