Supracondylar humerus fractures are common in children. Displaced fractures are usually treated with closed reduction and cross pin fixation. But, medial pinning may cause the ulnar nerve injury. The aim of this study was to compare the parents-based cosmetic satisfaction of the incision scars in children with displaced supracondylar humerus fractures treated by closed reduction and cross pin fixation with or without small medial incision. We retrospectively reviewed the medical records of 72 children with displaced supracondylar humerus fractures treated two different closed reduction and percutaneous pinning methods at our institution from January 2010 through December 2013. A group has 36 patients treated with small medial incision and crossed K-wires fixation after closed reduction. The other group has 36 patients treated with closed reduction and K-wires fixation. At the final follow-up, the patients were evaluated radiologically and clinically with Flynn's criteria. Furthermore, a visual analogue scale was used to determine of the parents-based cosmetic satisfaction score. All fractures healed without major complications at the final clinical and radiological assessment. Although, between the two groups did not differ in terms of Flynn cosmetic and functional outcomes, there were statistically significant differences between both groups according to the parents-based cosmetic satisfaction scores. The closed reduction and crossed pin fixation without small medial incision should be preferred first because of better the parents-based cosmetic satisfaction.