Abstract: Objective The purpose of this study is to evaluate the associations between FcγRⅡa and FcγRⅢa gene polymorphisms and Cetuximab-based treatment outcomes in metastatic colorectal cancer patients. Methods Eligible studies were searched from databases. Relative ratios （RR） with the corresponding 95% confidence interval （95%CI） were conducted. Statistical analysis was used with Stata 11.0. Results 12 articles were included, totally 1 016 cases. Pooled results indicated that no significant associations were found in FcγRⅡa and FcγRⅢa gene polymorphisms and Cetuximab-based treatment outcomes in metastatic colorectal cancer patients. In subgroup analysis, both KRAS and FcγRⅡa-H131R gene polymorphisms were significant association with Cetuximab-based treatment outcomes（RR vs. HH: RR=2.395,95%CI 1.522~3.771, I²=0.000; R vs. H: RR=2.072,95%CI 1.617~2.654, I²=0.457; HR+RR vs. HH: RR=3.067,95%CI 1.582~5.944, I²=0.692; HR vs. HH: RR=11.222,95%CI 1.324~95.106, I²=0.769）, while FcγRⅢa-V158F gene polymorphism was seemed to be associated with treatment outcomes in Asian（FF vs. VF+VV: RR=1.534,95%CI 1.138~2.069, I²=0.000; FF/VF: RR=1.398,95%CI 1.040~1.879, I²=0.000）. Conclusion FcγRⅡa and FcγRⅢa gene polymorphisms may be associated with Cetuximab-based treatment outcomes in metastatic colorectal cancer. Because racial differences and gene-to-gene interactions may influence such associations, more high-quality and large-scale studies are urgently needed.