Objective: To explore the risk factors of pregnancy-related venous thromboembolism ( VTE ) and the application effect of cluster prevention strategies. Methods: Twenty-one pregnant women hospitalized in our hospital from January 2017 to December 2018 and diagnosed with VTE were selected as a case group, and 63 non-VTE subjects were selected as a control group by 1:3 matching. The clinical data of the case group and the control group were collected. The logistic regression model was used to analyze the risk factors of VTE. The cluster prevention strategy was formulated and implemented according to the risk factors. The incidence of VTE in pregnant women before and after the implementation of cluster prevention strategy was compared. Results: Univariate and multivariate analysis showed that the advanced maternal age (OR=2.356, P=0.016), high BMI before pregnancy (OR=2.100, P=0.008), previous history of VTE (OR=1.931, P=0.023), gestational diabetes mellitus (OR=2.065, P=0.006), surgical operation during pregnancy or puerperium (OR=2.323, P=0.003), and high D-dimer level (OR=1.970, P=0.038) were the risk factors for VTE. After the implementation of the cluster prevention strategy, the incidence of VTE in 2019 was 0.03%, which was significantly lower than that in 2018 and 2017, and the differences were statistically significant (P=0.026, P=0.006, respectively). Conclusion: Advanced maternal age, high BMI before pregnancy, previous history of VTE, gestational diabetes mellitus, pregnancy or puerperium surgery are risk factors for pregnancy-related VTE, and cluster prevention strategies for these risk factors are helpful to reduce the incidence of pregnancy-related VTE.