Background The lateral femoral condyle (LFC) flap is a vascularized bone flap based on the superior lateral genicular artery (SLGA). Harvest technique for this flap has not yet been demonstrated. The purpose of this study was to better delineate the blood supply to the bone and skin of this flap to allow for a safe and effective harvest. Materials and methods Twenty-three lower extremities were injected with latex or a mixture of latex and barium sulfate. The SLGA was identified and dissected, documenting the course, diameter, anatomical relations, length, and branches. In the mixture group, high-resolution CT scanning was performed prior to dissection. Two additional specimens were dissected to illustrate the harvest technique. Results The SLGA originated from the popliteal artery at an average of 44.3 mm proximal to the knee joint line. The SLGA had an average diameter of 1.9 mm at origin and length of 56 mm. It coursed posterior to the femur, reaching the lateral intermuscular septum (IMS), dividing into superficial (patellar) and deep (condylar) branches, which coursed toward and gave branches to the patella and the LFC, respectively. At least one (average 1.4) septocutaneous skin perforator >5 mm emerged and ran posterior to the IMS. 3D reconstructions of the CT scans were used to confirm anatomic findings and describe a standard harvest technique. Conclusions The SLGA has consistent anatomy, adequate length, suitable diameter at origin for microvascular anastomosis, and constant perforators to bone and skin. The LFC flap provides a useful alternative to flaps from the medial knee or iliac crest.