PURPOSE: American Urological Association (AUA) antibiotic prophylaxis recommendations may be insufficient for covering organisms commonly found in penile prosthesis infections. In this study we assess the difference between AUA recommended antibiotic prophylaxis and nonstandard prophylaxis in preventing device infections in penile prosthesis surgery performed in diabetic patients. MATERIALS AND METHODS: A multicenter, retrospective cohort study of diabetic patients undergoing primary penile prosthesis surgery was performed between April 2003 and August 2018. Eighteen institutions from the United States, Europe and Korea contributed. The association between antibiotic prophylaxis type and postoperative penile prosthesis infections, device explantations and revision surgeries was assessed. RESULTS: Standard AUA antibiotic prophylaxis was followed in 48.6% (391) of cases while nonstandard prophylaxis was used in 51.4% (413). Common nonstandard antibiotic prophylaxis included vancomycin-gentamycin-fluoroquinolone, clindamycin-fluoroquinolone, and vancomycin-fluoroquinolone among other combinations. Patients who received AUA prophylaxis had significantly more postoperative device infections (5.6% vs 1.9%, p <0.01) and explantations (8.3% vs 2.0%, p <0.001) compared to those who received nonstandard prophylaxis. Patients who received AUA prophylaxis had significantly higher odds of a postoperative device infection (OR 2.8, 95% CI 1.1-7.3) and explantation (OR 3.6, 95% CI 1.4-9.1) compared to those who received nonstandard prophylaxis. CONCLUSIONS: Diabetic men with erectile dysfunction who received standard AUA prophylaxis for penile prosthesis surgery had significantly greater odds of experiencing a postoperative device infection and device explantation compared to patients who received nonstandard prophylaxis. Our study provides a strong rationale for a prospective investigation to establish the most appropriate prophylaxis strategy in penile prosthesis surgery.