The theoretical model of thermal-steady-state anisotropic 2 μm Tm∶YLF crystal was built based on the practical operation condition. Analytical solution was used to get the analytical expression of the distribution of temperature in Tm crystal and thermal focal length. Then,the influence of pump power,waist radius and crystal face size to the distribution of temperature and thermal focal length was simulated. The results show that the temperature rise and no uniformity of thermal distortion are intensified by the increase of doping density which leads to a worse thermal effect. The temperature rise and no uniformity of thermal distortion are weakened by the modest increase of crystal length which leads to a good thermal condition. The results in this paper provide theoretical basis for cavity design and cooling system of dual-pumped Tm∶YLF laser.