We searched the medical literature to review the evidence on the effects of pharmacological (drug), behavioural (behaviour change) and organisational (delivery of health care) interventions for the prevention of type 2 diabetes among people with mental disorders in low‐ and middle‐income countries (LMICs). Type 2 diabetes is a serious health condition that may develop when the body can no longer properly use a hormone called insulin. There are many reasons why a person may develop type 2 diabetes, including being overweight, having high blood pressure, not getting enough exercise, having a family history of the disease, and several other possible risk factors. We included randomized controlled trials (RCTs) published up to our search date, 20 February 2020.