Objective To characterize the early pain-induced thermal manifestations of knee joints, an accessible thermographic method for screening the abnormalities related to knee OA was developed. Methods One hundred and seventy-seven subjects were enrolled and the thermal images of knee joints were captured in China Rehabilitation Research Centre (CRRC). By quantitatively characterizing the temperature distributions and features of all the knee joints, a thermal screening method based on patella-centering was performed. Results Based on this method, the average screening accuracy rate of 91.6% (P<0.05) and sensitivity of 93.5% were obtained in distinguishing normal and abnormal cases. Conclusions This method shows high performance for screening the abnormal knee joints, which can be further utilized in the joint disease screening and physical examination.