This paper is addressed to the subject of suicide within both Hinayana and Mahayana traditions. The concept, type, and motive of suicide found in the canons of both traditions differ substantially. The relevant Hinayana and Mahayana doctrines are examined to explain their differences. The first section deals with suicide casea in the Agamas and Vinaya and explains why some cases were condoned while others censored. This section also investigates how Abhidharma literature treats the subject of suicide. The second indicates five kinds of motives in Mahayana suicide. Each is justified by its own doctrinal basis. The final section examines the attitude of some Chinese eminent Buddhists toward the controversial problem of religious suicide.