To compare gene expression profiles in response to estrogen or 17beta-estradiol (E(2)) and a mycotoxin, zearalenone (ZEA), and its analogues (collectively termed ZEA compounds), breast cancer MCF-7 cells were treated with 10 nM of E(2) or ZEA compounds including ZEA, alpha-zearalenol, beta-zearalenol, zearalanone, alpha-zearalanol and beta-zearalanol. Expression profiles for 120 estrogen-responsive genes were subjected to cluster and statistical analyses using correlation coefficients or R-values. We found that all of the ZEA compounds stimulated the growth of MCF-7 cells, as much as E(2), and showed similar expression profiles to that of E(2) (R-values ranged from 0.82 to 0.96). The effect of ZEA compounds was likely mediated by estrogen-receptor-dependent Erk1/2-signaling. These results provide clues to understand the mechanism of their estrogen-like action.