Purpose: To examine the topographic distribution of the origin of diabetic retinal neovascularization. Methods: The eyes of 3,121 patients with background diabetic retinopathy were investigated. These patients were volunteers in systemic medical therapy experiments. Color stereo photographs were obtained annually. The first retinal neovascularization sites were identified and the distances from the optic nerve measured. Results: In 1 year, neovascularization originated in 282 eyes. The superotemporal quadrant, at 6 mm from the optic disk, was the most frequent initial site. Conclusions: The first retinal neovascularization sites cluster around specific anatomic foci. This information should influence retinopathy monitoring protocols.