Objective To investigate the induction factors and prevention strategies for venous thromboembolism (VTE) during hospitalization in the intensive care unit (ICU) after heart valve replacement (HVR) in elderly patients. Methods A retrospective analysis was performed for 90 elderly patients who underwent HVR surgery in Department of Cardiac Surgery in our hospital from February 2020 to August 2022, and according to the presence or absence of VTE during postoperative ICU stay, the patients were divided into VTE group with 17 patients and non-VTE group with 73 patients. General data were collected and compared between the two groups, and the multivariate logistic regression analysis was performed for the items with statistical significance to explore corresponding preventive intervention strategies. Results There were no significant differences between the two groups in sex, heart rate, course of disease, liver cirrhosis, anemia, and atrial fibrillation (P>0.05), while there were significant differences between the two groups in comorbidity with hypertension or diabetes, time of operation, D-dimer level at 6 hours after surgery, duration of postoperative bed rest, body mass index (BMI), and past history of VTE (P<0.05). The logistic regression analysis showed that comorbidity with hypertension or diabetes, time of operation >1 hour, D-dimer level >480 μg/L at 6 hours after surgery, duration of postoperative bed rest >1 day, BMI >35 kg/m², and past history of VTE were associated with VTE after HVR surgery (P<0.05), and they were induction factors for VTE during postoperative ICU stay in elderly patients undergoing HVR. Conclusion Special attention should be paid to the elderly patients with hypertension, diabetes, time of operation >1 hour, D-dimer level >480 μg/L at 6 hours after surgery, duration of postoperative bed rest >1 day, BMI >35 kg/m², and past history of VTE after HVR surgery. Cardiac surgery nurses can take appropriate prevention strategies for these patients to reduce the risk of VTE after HVR.