Objective To explore the expression and significance of receptor activator of nuclear factor-KB(RANK)gene in 3T3-L1 adipocytes.Methods 33T3-L1 preadipocytes were selected to induce differentiation into adipocytes,and the RANK gene levels in adipocytes were measured using real time fluorescence quantita-tive polymerase chain reaction(qPCR).RANK knockout or overexpression 3T3-L1 cells were constructed,and were divided into 3T3-L1WT cells,3T3-L1RANK-KO cells,and 3T3-L1RANK-high cells.the changes in glucose consump-tion of adipocytes before and after RANK gene knockout were analyzed,and the expression of indicators relat-ed to fat browning,such as uncoupling protein 1(UCP1),CPT1B,and PPAR-γ,was analyzed.A high-fat diet rat model was established and the rats were divide it into a high-fat group and a high-fat exercise group.The relative expression levels of RANK and UCP1 proteins in brown adipose tissue were detected.Results Com-pared with 3T3-L1 preadipocytes,the relative expression levels of RANK and PPAR-γ genes increased in 3T3-L1 adipocytes(P＜0.05),and And the relative expression level of UCP1 gene decreased(P＜0.05).Com-pared with 3T3-L1WT cells,3T3-L1RANK-KO cells showed decreased glucose consumption,CPTIB,PPAR-γ,and UCP1 gene relative expression levels,and increased protein relative expression levels(P＜0.05),while 3T3-L1RANK-high cells showed decreased glucose consumption and UCP1 gene relative expression levels(P＜0.05).Compared with the high-fat group,the relative expression level of UCP1 protein in brown adipose tissue of high-fat exercise group rats increased(P＜0.05),while the relative expression level of RANK protein de-creased(P＜0.05).Conclusion RANK expression is upregulated in 3T3-L1 adipocytes and is involved in o-besity regulation.It mainly activates the NF-κB signaling pathway,inhibits UCP1,and causes white adipose tissue accumulation,thereby inducing the occurrence and development of obesity.