Studies have examined associations between obesity and suicide. However, the overall outcomes of the studies are not fully elucidated, and the orientation of these studies needs to be identified. The aim of this systematic review and meta-analysis was to determine the suicide risk based on body mass index (BMI).The authors systematically searched PubMed, Scopus, PsycInfo and Google Scholar databases until December 2017. After the screening process, 15 prospective studies were included in meta-analysis. Stata-14 was used for meta-analysis. Forest Plot was calculated for the whole of the 15 studies and the subgroups; publication bias was examined as well.In obesity group, Pooled Risk Ratio (RR) was achieved for suicide mortality (RR = 0.67; 95% confidence interval (CI) CI = 0.54–0.81) and suicidal ideation (RR = 1.50; 95% CI = 0.76–2.23). It was also measured in overweight group, for suicide mortality (RR = 0.78; 95% CI = 0.71–0.85) and suicidal ideation (RR = 1.17; 95% CI = 0.65–1.69).Overall, there is an inverse association between obesity and overweight with suicide mortality and attempted suicide, and positive association between obesity and overweight with suicidal ideation. There was no evidence of publication bias. Overall, our findings indicate the role of BMI in suicide.