A LD-pumped Nd:YAG, LBO (type-Ⅰ critical phase matching) intracavity frequency doubled, blue laser at 473 nm is reported in this paper. With the quasi-three-level model and a ordinary Nd:YAG rod as gain medium, by using a short three-folded-cavity resonator that is in sensitive to thermal effect, under the condition of 14 W pump power, high power TEM00 mode blue laser at 473 nm of 1.1 W is obtained at last, with the light-light conversion efficiency up to 7.9%, the threshold value is just 2 W. Moreover, the possibility of improving the power is discussed.