Objective To observe the expression of novel URB gene in the differentiation display of 3T3-L1 preadipocytes and the effects of interleukin-6 (IL-6) and pioglitazone (PIO) on URB mRNA expression in 3T3-L1 adipocytes at different times. Method The 3T3-L1 adipocytes were treated with IL-6 and PIO under different concentration and different time phase, and real-time fluorescence monitoring RT-PCR was conducted to measure the URB mRNA level. Fat droplets were verified by oil red O staining. Results 1. URB mRNA level was increased gradually in the whole differentiation process. 2. The expression levels of URB mRNA was decreased along with the treatment of IL-6 in a dose-dependent manner in 3T3-L1 preadipocytes and adipocytes. 3. PIO increased the level of URB mRNA in 3T3-L1 adipocytes, and the reducing effect of IL-6 on URB mRNA could be corrected by PIO. Conclusion URB may be an important adipocytokin which affects energy metabolism and may work as a pharmacological gene target in the future.