The output performance of a laser diode end-pumped continuous wave Tm，Ho∶YLF laser is studied and the laser parameters are optimized. Based the quasi-three-level rate equations，the relation formulus between the output power and the input power is deduced with consideration of the energy transfer up-conversion. The laser parameters such as the concentration of doped ions，the crystal length，the pump-to-mode size ratio and the transmittance of output coupler are optimized by numerical analysis. The output power as a function of pump power is obtained in experiment. Comparison of experimental and theoretical results shows that the theoretical results are valid.