This meta-analysis examined depression as a consequence of diabetes by conducting a meta-analysis, using data from longitudinal studies. Databases were systematically searched for relevant studies. Incidence of depression is presented as cumulative incident proportion (CIP). Pooled effect sizes were calculated using random-effects model. The data were reconstructed to compute relative risk (RR) and CIP. The 16 studies selected for review generated 16 datasets of which 11 studies reporting binary estimates (RR) and 5 studies reporting time-to-event estimates [hazard ratio (HR)]. Both RR and HR were significant at 1.27 (95 % CI 1.17–1.38) and 1.23 (95 % CI 1.08–1.40) for incident depression associated with diabetes mellitus. Our observations also revealed greater cumulative incidence of depression in diabetes than in non diabetes groups. Our study shows that diabetes is a significant risk factor for the onset of depression.