Screening asymptomatic men for prostate cancer is controversial and informed decision making is recommended. Within two prostate cancer screening programs, we evaluated the impact of a print-based decision aid (DA) on decision-making outcomes.Men (N=543) were 54.9 (SD=8.1) years old and 61% were African-American. The 2(booklet type: DA vs. usual care (UC))× 2(delivery mode: Home vs. Clinic) randomized controlled trial assessed decisional and screening outcomes at baseline, 2-months, and 13-months.Intention-to-treat linear regression analyses using generalized estimating equations revealed that DA participants reported improved knowledge relative to UC (B=.41, p<.05). For decisional conflict, per-protocol analyses revealed a group by time interaction (B=-.69, p<.05), indicating that DA participants were less likely to report decisional conflict at 2-months compared to UC participants (OR=.49, 95% CI: .26-.91, p<.05).This is the first randomized trial to evaluate a DA in the context of free mass screening, a challenging setting in which to make an informed decision. The DA was highly utilized by participants, improved knowledge and reduced decisional conflict.These results are valuable in understanding ways to improve the decisions of men who seek screening and can be easily implemented within many settings.