Based on the features of LD end-pumped Yb∶KGW laser crystal, the thermal model was established. Considering the convective heat transfer on the side faces, the temperature distribution, pumped-face distortion and thermal focal length under different pump power were obtained by solving anisotropy heat conductive equation through finite difference method. Under the pump power of 14 W, the highest temperature located at the center of the pumped face is 272.8 ℃,the highest distortion is 0.48 μm, and the thermal lens focal length at the pump spot is 4.8 cm.