Objective To generate mice with whole-body overexpression of human METRNL gene. Methods Based on Cre-loxP system, Dppa3-Cre mice were mated with Rosa26-LSL-METRNL knock-in mice(R26-LSL-METRNL+/-)to generate R26-L-METRNL+/- mice. The genotypes of the offsprings were identified, and tissues of the blood, heart, liver, spleen, lung, kidney, brain, white adipose and muscle were collected. The expression of human METRNL gene in mice was investigated by quantitative real-time PCR, western blot and enzyme linked immunosorbent assay. Results Compared with wild type control mice, human METRNL in R26-L-METRNL+/- mice significantly expressed at both mRNA and protein levels in tissues, with abundant METRNL protein in blood. Conclusion The mouse model overexpressing human METRNL gene(R26-L-METRNL+/- mouse)was successfully constructed.