Solid lubricants can improve the performance of planetary gear sets in extreme temperatures and complex mechanical environments. Severe gear wear will cause deterioration of performance, even failure. To evaluate the wear of gears, an improved wear prediction model for solid-lubricated planetary gear sets considering thermal effects and dynamics is proposed. First, a generalized dynamic model considering coating, wear and thermal effects is presented. For studying the thermal effects of gears, an improved thermal network model is developed, and the formula for thermal deformation is derived. Next, an improved wear model of gears is presented. Experiments are conducted to obtain the friction and wear coefficients of gears with MoS 2 coatings and to verify the proposed method. Finally, the coupling effects among wear, dynamics and temperature are examined. The results suggest that the proposed wear prediction method provides an improvement in wear prediction and contact pressure assessment at the pitch line. There is a competitive mechanism between wear and thermal effects. The contact pressure can be considered an indicator. Wear at the dedendum and addendum is more severe at low temperatures, owing to the dominance of thermal deformation at the beginning of wear. With progressive wear, the tooth contact pressure tends to be the same at different temperatures, after which wear becomes dominant. The coupling effects among dynamics, wear and thermal effects are analyzed in terms of time-domain, frequency-domain and statistics. At last, the coupling effects are further explained with the relative error of the meshing position. This study informs the predictive maintenance of coated gears.