This study was intended to investigate into the incidence rates of deep vein thrombosis (DVT) in patients who used prophylactic antithrombotic medications after total knee arthroplasty (TKA), and to compare clinical results in groups treated with Rivaroxaban versus Dalteparin sodium as prophylactic antithrombotic medications. This prospective study was performed in 300 patients who underwent TKA between November 2011 and December 2012. The prophylactic therapy was given to 150 patients in Rivaroxaban group and Dalteparin sodium group, respectively. In addition, intermittent compression pump and stocking were used in all the groups immediately after TKA. In order to determine the incidence of DVT, color Doppler ultrasonography, D-dimer, and clinical symptom examination were conducted. There were 17 cases (11.3%) of DVT in Rivaroxaban group and 18 cases (12.0%) of DVT in Dalteparin sodium group after TKA, and no significant difference was seen between both groups. Between patients with DVT and those without DVT after TKA at 4 days in both groups, there was a significant difference in the swelling indices. Moreover, a significant difference was observed in the evaluation of bruise. The early signs of DVT after TKA are unknown, however, some initial clinical signs such as swelling have been observed. After using the said prophylactic drugs, the lower incidence of DVT was seen, and there was no difference between the types of drugs. Pharmacological therapy (either Rivaroxaban or Dalteparin sodium) after TKA is considered effective for DVT prevention. There is also a need to consider constant monitoring of clinical symptoms.