Objective To develop an adult intraoperative hypothermia risk assessment scale, and to test its reliability and validity, so as to provide a scientific and effective assessment tool for nurses in operating room. Methods An item pool was constructed through literature review, which was used to form a draft scale after a two-rounds expert consultation, then the draft scale was used to investigate 150 elective surgery patients using convenient sampling to assess the risk of intraoperative hypothermia. The ROC curve was used to finally determine the risk threshold of the scale, the quartile method was used to classify its risk levels, and Cronbach′s alpha coefficient was used to test its reliability. Results The adult intraoperative hypothermia risk assessment scale included 2 dimensions and 10 risk factors. Its risk threshold was 15 points, ROC curve was 0.820, and its sensitivity was 100%， specificity was 47.52%. The risk assessment 15-16 points was defined low risk, 17-20 points was medium risk, >20 points was high risk. The Cronbach′s alpha coefficient of the scale was 0.780. Conclusion The adult intraoperative hypothermia risk assessment scale displays good predictive performance, so it can be utilized for assessing adult intraoperative hypothermia risk.