This review investigated the effectiveness of adjuvant therapy combined with constraint-induced movement therapy (CIMT) in improving the paretic upper limb functionality in adults with stroke sequelae during the subacute to chronic rehabilitation phase. In this systematic review and meta-analysis of randomized controlled trials (RCT), electronic databases, including PubMed, Web of Science, CINAHL, and MEDLINE, were searched. We included RCTs that investigated the outcomes of adjuvant therapy (i.e. other therapies) added to CIMT compared with CIMT alone. Key trial findings were qualitatively synthesized and analyzed. This meta-analysis examined variables, such as mean scores and standard deviations, using the following outcome measures: Fugl-Meyer Assessment (FMA) upper limb items, Action Research Arm Test (ARAT), Amount of Use (AOU) of Motor Activity Log (MAL), and Quality of Movement (QOM) of MAL. Eighteen eligible RCTs were included in the analysis. Adding CIMT to adjunctive therapy significantly improved FMA compared with CIMT alone (mean difference [MD] 4.02, 95% confidence interval [CI] 2.60-5.44; I² = 85%; 15 studies; 330 participants). Similarly, the ARAT and MAL-AOU scores improved significantly. CIMT combined with several adjunctive therapies effectively improved upper limb function.