Inappropriate heat and mass transfer is an extremely important factor to cause rheumatics of human knee which however receives few attentions up to now. Understanding the thermal behaviors of pathological knee tissues can help diagnose its pathological status and find out the most efficient therapeutical way, which is hard to access otherwise. This paper is dedicated to develop a theoretical model for characterizing the three-dimensional temperature fields of human knee by taking its real anatomical structure into consideration. Based on the classical Pennes bioheat transfer equation, the temperature fields of normal knees and pathological ones under various thermal conditions were numerically simulated and compared, which would help better understand the disease mechanisms causing trouble for human knee. Meanwhile, a medical infrared image system was adopted to map the surface temperature of human knee which qualitatively verifies the theoretical prediction and its diagnostic value. Further, effects of heating from outside on the knee tissue and interventional hyperthermia based on vessel heating were also evaluated. Potential therapeutical strategies were suggested for the thermal rehabilitation of rheumatic knee in the near future.