To research and develop a compact ultraviolet laser with high stability and high efficiency,a mini type all-solid-state ultraviolet laser device at 355nm is obtained with laser -diode end-pumped Nd:YVO_4crystal,intracavity frequency doubling and tripling employing two LiB₃O₅(LB O) crystals with angle phase matching between of type Ⅰ and type Ⅱ,respectively.To enhance conversion effic iency in the experiment,the temperature of the frequency conversion crystals is accurately adjusted by emplo ying proportion integration differentiation (PID) digital temperature control modules with resol ution of ±0.01℃ to compensate the angle phase mismatch,which are led in by the fixed crystal clamps .Output performance of the 355nm laser is as follows:at repetition frequency of 15kHz,the average o utput power is 1.24W at the pump power of 13.33W,output wavelength of the pump source is 804nm not at the absorption peak of Nd:YVO_4crystal of 808nm,the conversion efficiency from diode laser t o ultraviolet laser is about 9.3%,pulse duration is of 9.8ns,beam quality factors are M 2_x＝1．8,M²_y＝1．7 and the power instability is 0.45% within 2h operation.By adjusting the temperature to c ompensate for the angle phase mismatch of the nonlinear crystals,a compact no-water-cooling ultraviolet laser with high stability and high conversion efficiency can be obta ined.