Objective To explore appropriate selection strategies for anticoagulants subcutaneous injection sites in patients with lower extremity deep vein thrombosis (DVT) during the third trimester of pregnancy, and to provide evidence for standardization of the nursing cooperation process. Methods A total of 46 women diagnosed with lower extremity DVT during the third trimester of pregnancy and in need of subcutaneous injection of anticoagulants were randomized into 2 groups of 23 each.In the observation group, the abdominal wall was divided into 8 parts (bilateral upper anterior, lower anterior, upper medial and lower medial), then the thickness of the subcutaneous tissue in each part was determinedby doppler ultrasound; after that, the 8 parts were rotated to receive subcutaneous injection of anticoagulants on the condition of safe needle insertion depth.In the control group, middle and posterior regions of the deltoid muscle were alternated as injection sites.The degrees of local pain immediately after injection, and two hours after injection were evaluated by Numeric Rating Scale （NRS）. The incidence rates of subcutaneous ecchymosis and induration, along with the changes in activated partial thromboplastin time （APTT） were observed. Results The NRS pain scores imme-diately after injection, and two hours after injection, and the incidence rates of subcutaneous ecchymosis and induration in the observation group were significantly lower than those of the control group （P＜0.01 for all）, whereas, pre-and post treatment APTT showed no significant difference between the two groups （P＞0.05）. Conclusion Modified subcutaneous injection of anti-coagulants at 8 outer parts (avoiding the peri-umbilical region and within 10 cm around the umbilicus) of the abdominal wall,is a safe and feasible for women developing DVT in the third trimester of pregnancy.