ABSTRACT: Background:Antipsychotic-induced weight gain (AIWG) is a crucial factor for the medication cessation of patients with schizophrenia. Multiple studies have shown that the functional polymorphism -759?C/T (rs3813929) in the HTR2C promoter region could possibly be correlated with AIWG. Aim:To evaluate the genetic association of the HTR2C-759C/T polymorphism and AIWG in patients with schizophrenia with antipsychotic drugs (APDs) administration. Methods:Eligible studies were identified by searching the following databases: PubMed, Embase, Web of Science, China Nation Knowledge Infrastructure (CNKI), VIP, Wanfang Data, Chinese Biomedical Literature Database (CBM) and the Airiti Library. The quality of studies was evaluated based on the Newcastle-Ottawa Scale. The pooled OR and 95% CI were calculated for the dominant (CT/TT/T vs CC/C) mode, and subgroup analyses were performed based on ethnicity, antipsychotic medication and gender; all statistical analyses were performed using the statistical software STATA V.12.0. Result:A total of 17 studies with 3170 patients with schizophrenia were included in our meta-analysis. The result of the meta-analysis has shown that the association between the -759?C/T polymorphism and AIWG is statistically significant (OR 0.34, 95%?CI: 0.20 to 0.57, z=4.11, p<0.001). The subgroup analyses revealed significant correlations between the -759?C/T polymorphism and AIWG in the Caucasian population (OR 0.33, 95%?CI: 0.14 to 0.77, z=2.55, p=0.011), the Asian population (OR 0.31, 95%?CI: 0.18 to 0.52, z=4.46, p<0.001), the patients with APDs administration (CT/TT/T vs CC/C: OR 0.63, 95%?CI: 0.40 to 1.00, z=1.97, p=0.049) and the patients with atypical antipsychotic drug administration (CT/TT/T vs CC/C: OR 0.21, 95%?CI: 0.09 to 0.47, z=3.83, p<0.001). The sensitivity analysis showed that the results were stable. Begg's test (after correction z=1.07, p=0.287) and Egger's test (t=-2.41, p=0.029) show that the included articles have no significant publication bias. Conclusion:There is a significant genetic association between HTR2C-759C/T and AIWG, and patients with T allele are less likely to have AIWG.