Background: When people require medical treatment, many risk factors including adverse medical events, economic burdens, and social-psychological consequences may contribute to their hesitation to seek medical help. Therefore, a reliable and valid instrument that can comprehensively assess the risk perception of medical help-seeking behavior among ordinary Chinese adults should be developed. Methods:The basic dimensions of the scale were determined based on literature review and in-depth interviews with patients. Then, an item pool with 32 items and six dimensions was developed. After the item reduction process based on item and factor analyses, a three-factor, 16-item scale was established. From March 2019, this scale was distributed among 639 healthy adults, outpatients, or inpatients in 20 provinces and municipalities in the mainland of China by convenience sampling. Then, the reliability and validity of the scale were examined. Results:The scale consists of three dimensions (treatment risks, burden risks, and stigma risks) and 16 items. The root-mean-square error of approximation, comparative fit index, and Tucker-Lewis index of this model were 0.069, 0.925, and 0.910, respectively. The internal consistency reliability of the scale was 0.893, and the test-retest reliability was 0.784. The criterion-related validity was 0.720 (P<0.01). Conclusions:The risk perception scale of medical help-seeking behavior is a reliable and valid instrument to measure Chinese adults' perception for potential risks in the process of medical treatment.