To clarify the function of miR-103 in the differentiation of porcine preadipocyte , we carried out real-time PCR to detect the expression pattern of miR-103 during adipogenesis, and clarified its expression tendency through cell differentiation. Then we used adenovirus that overexpressed miR-103 to infect porcine preadipocyte. Subsequently, mRNA and protein expression of adipogenesis marker—PPARγ and aP2 was analyzed by real-time PCR and Western blotting. At last, Oil-Red O staining was used to detect lipids accumulation in the 8th day after adipogenic inducement. The expression of miR-103 increased during adipocyte differentiation; compared with the control, the preadipocyte infected by pAd-miR-103 had an elevated expression level of adipocyte marker gene PPARγ, aP2, and obvious lipid droplet was seen in the 8th day after adipogenic inducement. These results showed that miR-103 can enhance adipogenesis in primary cultured porcine adipocytes.