A design of LD-pumped Nd∶YVO_4/LBO blue laser at 457 nm is presented in the paper.An optimized-designedCW914nmlaseratroomtemperatureisobtained.Usingtype-Icriticialphase-matchingLBOcrystal,457nm blue laser is obtained by 914 nm intracavity frequency doubling. The maximum laser output power of 20 mW is obtained when a incident pump laser of 1.7 W is used. The optical-to-optical conversion is up to 1.2%, the power instability in 24 h is better than ±3%.