Background:Adjunctive psychological interventions for bipolar disorder have demonstrated better efficacy in preventing or delaying relapse and improving outcomes compared with pharmacotherapy alone. Aims:To evaluate the efficacy of psychological interventions for bipolar disorder in low- and middle-income countries. Method:A systematic review was conducted using PubMed, PsycINFO, Medline, EMBASE, Cochrane database for systematic review, Cochrane central register of controlled trials, Latin America and Caribbean Center on Health Science Literature and African Journals Online databases with no restriction of language or year of publication. Methodological heterogeneity of studies precluded meta-analysis. Results:A total of 18 adjunctive studies were identified: psychoeducation (n = 14), family intervention (n = 1), group cognitive-behavioural therapy (CBT) (n = 2) and group mindfulness-based cognitive therapy (MBCT) (n = 1). In total, 16 of the 18 studies were from upper-middle-income countries and none from low-income countries. All used mental health specialists or experienced therapists to deliver the intervention. Most of the studies have moderately high risk of bias. Psychoeducation improved treatment adherence, knowledge of and attitudes towards bipolar disorder and quality of life, and led to decreased relapse rates and hospital admissions. Family psychoeducation prevented relapse, decreased hospital admissions and improved medication adherence. CBT reduced both depressive and manic symptoms. MBCT reduced emotional dysregulation. Conclusions:Adjunctive psychological interventions alongside pharmacotherapy appear to improve the clinical outcome and quality of life of people with bipolar disorder in middle-income countries. Further studies are required to investigate contextual adaptation and the role of non-specialists in the provision of psychological interventions to ensure scalability and the efficacy of these interventions in low-income country settings. Declaration of interest:None.