Two cases of the management and pathophysiology of high flow arterial priapism are presented. Both cases were post-traumatic with delayed onset of priapism and both had angiographically diagnosed arteriocorporeal fistulas. Case 1 was managed with selective cavernous artery ligation and case 2 resolved spontaneously, both with excellent return of premorbid levels of erectile function. We propose that the pathophysiological mechanism involves injury to the intracavernous artery, causing ischemic necrosis. After a delay the arterial segment blows out, leading to unregulated blood flow into the corpus cavernosum. Management with surgical ligation is highly selective and nondisruptive to unaffected vessels, offering precise control of the bleeding vessel.