Comparative studies on the thermal effect and laser performance of diode-end-pumped Nd∶YAG crystals at 946 nm are presented. The temperature of end surfaces and thermal lensing of crystals are measured. When the absorbed pumping power reaches 10 W, the end surface temperature of the atomic fraction of 1.0% doped composite crystal is 25.9 ℃, which is only 1/3 of that of 1.0% non-composite crystal. Morever, the composite crystal can relieve the thermal lensing effect under the same condition. A compensation of the thermal effects in electro- optical crystals is achieved by employing a quarter-wave plate, which allows for the production of an electro-optically Q-switched 946 nm Nd∶YAG laser at 1 kHz. A maximum output power of 350 mW and 17 ns pulse duration laser is achieved with the atomic fraction of 0.5% doped composite crystal under the incident pumping power of 10.4 W. The power stability is 2.7% . The maximum output power is more than three times higher than that of a noncomposite crystal and two times than that of a atomic fraction of 1.0% doped composite crystal.