The laser diode array (LDA) end-pumped intracavity doubling frequency high power blue laser is reported. Gain medium is composited Nd:YAG crystal, the temperature of which is precisely controlled by thermoelectrically cooled (TEC). The doubling frequency crystal used in the experiment is a LBO (LiB2O3) crystal cut in phase-matching type Ⅰ. The cavity is V type. This cavity is designed based on the facts that the thermal-lensing effect of the rod pumped by high pumped power is serious and the focal length of the thermal lens becomes shorter when the pumped power increases. According to the highest pumped power, the cavity is optimized so that the optimum mode-matched and high conversion efficiency are realized. When absorbed pumped power is 18.5 W, the blue laser output power at 473 nm is 1.38 W and the conversion efficiency of pumped light to doubling frequency light is 7.5%. The laser is simple and stable in structure.