Epidemiological studies have shown marked variations in prostate cancer incidence and mortality across different geographic regions, leading to the rising interest in the role of nutrition in prostate cancer risk. There is also a large body of evidence that a diverse diet, rich in vegetables, can reduce the risk of prostate cancer. In this review, the role of various kinds of vegetables and their bioactive compounds associated with prostate cancer risk, and the underlying mechanisms of these associations are summarized. There is accumulating evidence to support the consumption of lycopene, in particular tomato and tomato-based products, as protective factors against prostate cancer. Evidence on the protective role of beta-carotene was inconsistent from cohort and case-control studies. Evidence on the effect of pulses or soy consumption on prostate cancer risk was limited but suggestive of decreased risk with increased pulses or soy consumption. However, the role of vitamin C, vitamin E, allium vegetables, and cruciferous vegetables on prostate cancer risk remains to be determined due to limited evidence. Although the impact on prostate cancer risk differs among various vegetables and their constituent nutrients, the overall benefits of plant based diet on cancer prevention and other diet-related diseases should be promoted.