Abstract: To investigate the effects of serum on the preadipocyte during the process of induced differentiation and describe the expression patterns of genes related to adipogenesis in porcine, preadipocytes were isolated from subcutaneous adipose tissue of two days old piglets (Large White × Rongchang pigs) by using collagenasedigestion approach. The preadipocytes were cultured in different media supplemented with 50 nmol·L1 insulin, 100 nmol·L1 dexamethasone, 0.25 mmol·L1 1methyl3isobutylxanthine and 100 nmol·L1 rosiglitazone. In addition, the different effects between the two methods were also been compared, which included the effects of serum (control group) and serumfree (experimental group) on differentiation of preadipocytes, respectively. Total RNA were extracted from the cells and the mRNA expression level of genes involved in adipogenesis were measured by realtime quantitative RTPCR method. The results indicated that the mRNA expression levels of PPARα, C/EBPα, FASN, ACOX1, GPAT and ENPP2 were significantly downregulated (P<0.01) under the condition of serum added, in contrast, the mRNA expression level of PPARγ and FABP4 were significantly upregulated (P<001). The mRNA expression level of FASN, GPAT and ACOX1 in the experimental group were higher than that in the contrast group at P<0.01 level. Strikingly, the significant positive correlations among the mRNA expression levels of PPARα, PPARγ, C/EBPα and ACOX1 were observed in the experimental group. The results indicated that the serum has a fairly strong inhibitory discoloring effect on porcine preadipocyte during the process of induced differentiation. PPARα, PPARγ, C/EBPα and ACOX1 have the similar expression patterns. The serum is essential to accelerate the deposition of intracellular fat.