This article documents the first case report of an extended hemipelvectomy defect closure using an ipsilateral external oblique myocutaneous flap. When a hemipelvectomy usually is performed for soft tissue tumor ablation, an anterior or posterior flap can be preserved for immediate coverage of vital structures. When these flaps are also resected to obtain clear tumor margins, closure becomes difficult. In our patient, although the rectus myocutaneous flap was a next logical choice, prior surgical scars precluded it use. The external oblique flap was successfully rotated and solved a difficult problem. This flap should be considered when the rectus abdominis myocutaneous flap is unavailable for extended hemipelvectomy closures.