Abstract:[Objective] To explore the risk factors for symptomatic deep vein thrombosis (DVT) after total knee arthroplasty (TKA). [Methods] A total of 926 patients who underwent TKA in the First People's Hospital of Zunyi City from 2018 to 2023 were included in the study. The occurrence of DVT was determined by clinical and ultrasound and the risk factors for DVT occurrence were searched by using univariate comparison and multiple logistic regression analysis. [Results] Among 926 patients, 76 were diagnosed with symptomatic DVT by postoperative clinical and ultrasound examinations, with an incidence of 8.2% (76/926); while 1 case was diagnosed with pulmonary embolism by pulmonary artery CTA examination, with an incidence of 0.1% (1/926). Regarding univariate comparison, the DVT group proved significantly greater in terms of proportion of male [male/female, (23/53) vs (147/703), P=0.006], the proportion of smokers [yes/no, (14/62) vs (75/775), P=0.008], concomitant hypertension [yes/no, (50/26) vs (413/437), P=0.004], arrhythmia [yes/no, (7/69) vs (33/817), P=0.029], and lower limb venous valve dysfunction [yes/no, (57/19) vs (488/362), P=0.004], and intraoperative blood loss [(151.4±77.9) ml vs (136.0±62.3) ml, P=0.045], platelet/lymphocyte ratio (PLR) [(168.5±96.3) vs (135.5±59.7), P=0.045], neutrophil/lymphocyte ratio (NLR) [(2.9±2.0) vs (2.3±1.7), P=0.010], ESR [(20.6±19.2) mm/h vs (15.7±11.7) mm/h, P=0.002], PT [(11.5±1.3) s vs (11.3±0.8) s, P=0.007], Fbg [(3.6±2.2) g/L vs (3.0±0.7) g/L, P<0.001], CRP [(21.8±27.4) mg/L vs (12.6±7.4) mg/L, P<0.001], while significantly less in terms of INR [(1.0±0.1)% vs (1.1±0.1)%, P=0.007] and TT [(16.6±2.0) s vs (17.0±1.1) s, P=0.030] than the asymptomatic group. As results of multivariate logistic regression, smoking (OR=2.330, P=0.008), lower limb venous valve insufficiency (OR=2.230, P=0.027), PLR (OR=1.840, P<0.001), hypertension (OR=1.240, P<0.001), and CRP (OR=1.040, P=0.031) were risk factors for symptomatic DVT after TKA. [Conclusion] This study found that smoking, lower limb venous valve insufficiency, PLR, hypertension, and CRP are risk factors for symptomatic DVT after TKA, which should be noted by clinicians.