The existence of cyclic depsipeptide mycotoxins in foods and feedstuffs could cause endocrine disrupting effects on humans and wildlife by their inhibition of active steroidogenesis. Therefore, we tried to measure the human oestrogen receptor (ER) and androgen receptor (AR) agonistic/hostile results of representative cyclic depsipeptide mycotoxins, enniatin A1 (ENN A1), and enniatin B1 (ENN B1), by OECD Performand Based Test Guideline (PBTG) No.455, VM7Luc ER transcriptional activation (TA) assay and OECD TG No. 458, 22Rv1/MMTV_GR-KO AR TA assay. No tested cyclic depsipeptide mycotoxins were discovered to be ER and AR agonists in VM7Luc ER TA and 22Rv1/MMTV_GR-KO AR TA assays. However, ENN A1, and ENN B1 exhibited the ER and AR hostile effects with IC30 and IC50 values both in TA assays. Both of these cyclic depsipeptide mycotoxins, that have been determined as ER and AR antagonists by two in vitro assays, certain to ER|¨¢, and AR. Then ENN A1, and ENN B1 inhibited the dimerization of ER|¨¢, and AR. These results, the very first time established that ENN A1, and ENN B1 might have potential endocrine disrupting effects mediated by interaction of ER|¨¢ and AR using worldwide standard testing methods to look for the potential endocrine disrupting chemical.