In this study, the heat distributions of MgO∶PPLN crystals under different incident pump optical radii are simulated and analyzed. Considering the temperature rise phenomenon near the central axis of the crystal during operation, the crystal heating parameter t is added to optimize the crystal temperature tuning curve. The inverse conversion phenomenon of MgO∶PPLN optical parametric oscillation (OPO) is experimentally analyzed. Furthermore, the relationship between the parametric light reflectance of the cavity mirror and the optimal pump super-threshold multiple is investigated, and the effect of crystal length on the OPO conversion efficiency is analyzed. By optimizing the experiments, the continuous change range of the signal light wavelength in the temperature range of 30-190 °C is measured to be 1568.9-1659.8 nm. At a pump power of 1.12 W, repetition frequency of 15 kHz, and temperature of 90 °C, the obtained near-infrared laser output is 1595 nm with a maximum average power of 110 mW.