There is considerable interest in exploring effects of coronavirus disease 2019 (COVID-19) pandemic on mental health. Suicide is one of the leading causes of mortality worldwide and changes in daily life brought by the pandemic may be additional risk factors in people with pre-existing mental disorders. This rapid PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) scoping review aims to identify and analyze current evidence about the relation between COVID-19 pandemic outbreak, along with COVID-19 disease and severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection, and suicide in individuals with previously diagnosed mental disorders. First, we conducted a comprehensive review of the literature, then proceeded to discuss findings in a narrative way. Tables were constructed and articles sorted according to the studies' methodologies. 53 papers were eventually identified as eligible, among which 33 are cross-sectional studies, 9 are longitudinal studies, and 11 studies using other methodologies. Despite suffering from a mental disorder is a risk factor for suicidal behavior per se, the advent of COVID-19 pandemic may exacerbate this relation. Nevertheless, data addressing a clear correlation between suicidal behavior and the pandemic outbreak are still controversial. Longitudinal analysis using validated suicide scales and multicenter studies could provide deeper insight and knowledge about this topic.