Traditional methods of correcting malunited distal humeral fractures in children involve complex wedge osteotomies held with pins or internal fixation devices. These require a large exposure and challenging fixation. We elected to perform simple transverse osteotomies, without wedges, using a lateral incision. These were maintained by the small AO external fixator. Between 1987 and 2004, five children with malunited distal humeral fractures were treated. Angular and rotational correction was obtained in each case. Bony union occurred at an average of 8 weeks. A simple osteotomy held by the small AO external fixator provides accurate correction, precise adjustability, and solid stability.