Objective To evaluate the effect of a suicide prevention gatekeeper training program for oncology nurses, and to enhance nurses′ ability of suicidal behavior prevention. Methods Fifty-six oncology nurses received four training sessions developed by referring LivingWorks training system and related literature on suicidology and oncopsychology.Nurses were taught about basic know-ledge of suicide prevention, risk assessment, suicide intervention, follow-up and post growth. Results The total suicide prevention gatekeeper self-efficacy score, total and dimension scores of awareness of suicide warning signs, as well as the correct rates of suicide prevention knowledge were significantly enhanced after the training （P＜0.05,P＜0.01）. Conclusion Suicide prevention gatekeeper training can enhance oncology nurses′ self-efficacy, ability to identify suicide warning signs, and knowledge of suicide prevention.