Objective To investigate the effect of hyperhomocysteine on deep vein thrombosis (DVT) after orthopedic surgery. Methods The clinical data of 149 orthopedic patients who underwent DVT in Xi'an Honghui Hospital from January 2018 to April 2019 were retrospectively analyzed. According to the preoperative homocysteine (Hcy) level, the patients were divided into high homocysteine group and normal group. According to the postoperative ultrasound results, they were divided into DVT group (preoperative no postoperative) and non DVT group (preoperative none postoperative), excluding preoperative blood Thrombus patients. The difference of Hcy value between each group was compared. The relationship between DVT and HHcy was evaluated. The predictive value of HHcy for DVT occurrence was further evaluated, and the correlation between them was analyzed. Results Among the 149 patients, 68 were male and 81 were female, 69 were DVT patients, 54 were nonDVT patients, 97 were HHcy patients, and 52 were normal Hcy patients. Age and gender were not statistically significant between the groups (P＞0.05). In the subgroup analysis of DVT, there was a significant difference in Hcy value (247±142) mol/L between DVT group and nonDVT group (148±67) (P＜0001), but there was no statistical significance between Hcy value and thrombus width (P=0553). The incidence of the HHcy group was higher than that in the normal Hcy group (812% vs 188%) (P＜0001). DVT was significantly correlated with Hcy level (P＜0001). ROC curve analysis showed that HHcy had good accuracy in predicting DVT after orthopaedic surgery (AUC 0750). Logistic regression analysis showed that Hcy was the independent variable and the occurrence of DVT was the dependent variable. Exp(B), OR was 5385, P=0000＜0.05, which suggested that HHcy was correlated with the occurrence of postoperative DVT.Conclusion Hyperhomocysteinemia has an effect on the incidence of DVT after orthopedic surgery, and there is a correlation between the two, but the value of homocysteine has no obvious correlation with the width and diameter of the thrombus. Hyperhomocysteinemia can be used as one of the diagnostic markers to predict DVT after orthopedic surgery.