PURPOSE: We have performed total knee arthroplasty for treating valgus and varus in the knees of one person. We investigated the clinical characteristics of these patients and the relationship between the kind of deformity and the postoperative result. MATERIALS AND METHODS: From March 2002 to May 2005, fourteen patients who had simultaneous varus and valgus knee deformities underwent total knee arthroplasties and they were followed for more than 12 months, and these were the subjects of our study. The average age was 64.6.years and the average follow-up period was 18.4 months. Follow-up imaging assessments were done and the clinical outcomes were evaluated using the HSS score at the last follow-up. RESULTS: Nine cases had more pain in the varus knee preoperatively and two cases had more pain in the valgus knee preoperatively. In 8 cases, degenerative scoliosises were associated with the knee deformity and among these cases, seven cases had vlagus deformities in the right knees. In two cases, hip deformities were noted in the ipsilateral side of the valgus deformity. The preoperative mean valgus angle and varus angle was 10.5 degrees and 7.8 degrees, respectively. The postoperative valgus and varus angle improved to 6.8 and 6.0 degree, respectively. The HSS score improved from 64.7 to 86.0 points for the valgus deformities and from 61.5 to 86.9 points for the varus deformities. Postoperative patellar clunk syndrome was identified in one valgus knee and arthroscopic resection was then performed. The knee had completely recovered on the last follow-up. CONCLUSION: Simultaneous or staged total knee arthroplasties in patients with simultaneous varus and contralateral valgus knee deformities achieved satisfactory outcomes with regard to the objective orthopedic criteria as well as the overall patient satisfaction in terms of pain relief and function. We found that scoliosis and ipsilateral hip deformities concurred with knee deformities, and this indicated that hip deformity and scoliosis are related with knee deformities. We found no significant difference between the kind of deformity and the postoperative result, yet a prospective study with more cases and longer follow-up is recommended in the future to reaffirm our findings.