Objective To develop an Assessment Scale of Venous Thromboembolism Risk Perception and Health Behavior Decision for Pregnant Women, and test its reliability and validity, so as to provide reference for accurately assessing the level of pregnant women′s risk perception of venous thromboembolism and health behavior, as well as carrying out health behavior intervention. Methods The pool of scale items was initially constructed through a literature review and semi-structured interviews. The initial scale was formed after two rounds of expert consultation, and the expressions of items were adjusted through a pre-survey to form the test version of the scale. A convenience sampling method was adopted to select 663 pregnant women for a questionnaire survey to test the reliability and validity of the scale. Results The Assessment Scale of Venous Thromboembolism Risk Perception and Health Behavior Decision for Pregnant Women included 6 dimensions and 53 items.Exploratory factor analysis extracted 6 common factors, and the cumulative variance contribution rate was 81.618%. Confirmatory factor analysis showed that χ2/df=2.846,RMR=0.022,RMSEA=0.075,TLI=0.912,CFI=0.921,IFI=0.921. The Cronbach′s α coefficient of the total scale was 0.987, the split-half reliability was 0.889, and the test-retest reliability was 0.906. The S-CVI/Ave was 0.993, and the I-CVI was between 0.900 and 1.000. Conclusion The Assessment Scale of Venous Thromboembolism Risk Perception and Health Behavior Decision for Pregnant Women has good reliability and validity, and it can be used to evaluate the level of venous thromboembolism risk perception and health behavior of pregnant women.