Cubitus varus deformity is the most common late complication of malunited supracondylar fracture that requires corrective osteotomy and fixation. From 2009 to 2017, 40 consecutive patients with cubitus varus deformity were included. Twenty patients underwent the conventional closing-wedge osteotomy (conventional group), while the other twenty patients underwent the 3D-printed model and osteotomy template osteotomy (3D-printed template group). The functional outcome was evaluated using the Mayo Elbow Performance Index (MEPI) Score and Flynn criteria. There were no statistically significant differences were observed regarding the humerus-elbow-wrist angle and tilting angle between the two groups, both preoperatively and postoperatively at 24 months. No statistically significant differences were observed regarding the elbow ROM (127.0 ± 4.7° VS 128.9 ± 3.8°) and MEPI score (93.5 ± 3.3 VS 94.3 ± 4.1) between the groups. All patients were satisfied both cosmetically and functionally as per the Flynn criteria and MEPI score. The conventional osteotomy and 3D-printed model and osteotomy template techniques both met the treatment requirements of cubitus varus deformity. The 3D-printed template technique showed better osteotomy accuracy, but no significant advantage regarding the functional and cosmetic results than conventional osteotomy.