Mental health is a key issue for populations affected by conflict. The evidence base on the mental health of internally displaced Colombians is undefined, as well as protective strategies utilised by this group. This systematic literature review aims to identify and assess the evidence base on the mental health of Colombian internally displaced persons (IDPs). Specific objectives are to examine (1) prevalence and incidence rates of common mental disorders (CMDs) amongst adult Colombian IDPs, (2) risk factors associated with CMDs amongst this group, and (3) coping strategies used by these displaced persons. A database search was conducted in May 2021. Included studies reported quantitative and/or qualitative mental health outcomes of CMDs, and/or coping strategies, among Colombian IDPs. The search yielded 34 articles. Study quality ranged from adequate to poor, with several containing serious shortcomings. PTSD prevalence ranged from 1.2%-97.3%, anxiety from 0.0%-60.0%, depression from 5.1%-100%, and problematic alcohol use from 8.0%-33.5%. Factors significantly associated with CMDs were inconsistent. Seeking social support and problem-solving strategies were the two most-commonly reported coping strategies. Associations between mental health and coping were largely unreported. As the evidence base is weak, there is a clear need for better quality research in this area.