We attempted in this study to investigate the prevalence of Peyronie's disease (PD) among diabetic patients with erectile dysfunction (ED). Two-hundred and six diabetic patients were further evaluated in this study. Forty-two (20.3%) patients had PD. There were significant associations between PD and risk factors of age, obesity and smoking. All patients with PD had also ED. Penile curvature was present in 82.1% of all patients with PD. Of the patients with PD, 25.4% had pain with or without erection. Significant associations between PD and ED and ED duration were detected. This study confirmed the high prevalence of PD among diabetic patients with ED. Further work is needed probing the mechanisms through which diabetes affects the pathogenesis of ED and PD.