Phthalates, suspected endocrine disruptor, are plasticizer and solvent used in industry, and some phthalates are known as potential carcinogen. Most common human exposure to this compounds may occur with contaminated food. It may migrate into food from plastic wrap or may enter food from general environmental contamination, and it has become widespread environmental pollutants, thus leading to a variety of phthalates that possibly threaten the public health. Dibutyl phthalate (DBP) may play a part of cell proliferator, which mediates changes in gene expression and the metabolism of xenobiotics. An understanding of the role of DBP in modulating gene regulation should provide insight regarding mechanisms of DBP induced xenoestrogenic impact. To elucidate the type of genes that are associated with estrogenic activity induced by DBP at the dose (10-8 M) appeared proliferating effects, the pattern of gene expression in MCF7 cells was compared between 17β-estradiol and DBP exposure in the cDNA microarray. From the results, it showed some differences of gene expression patterns between MCF7 cells treated with 17β-estradiol and DBP, and also DBP shows estrogenic potential with changes in estrogen-related gene expression levels.