Mycotoxins especially aflatoxin B₁ and zearalenonecausea wide range of harmful effects in farm animals. The problems of mycotoxins are not only just end in the harmful effect on animal performance but also many of them become concentrated in milk and can pose a threat to human health. So, this study aimed to investigate the effect of using mycotoxin deactivator inlactating animal ration to reducing the harmful effect of micotoxins on animal performance and milk safety. A total of twentyfour primiparous and multiparous Holstein lactating cows were assigned to two groups of twelve cows each. The experiment was extended for one month and the animals were fed total mixed ration (TMR) in quantities suffusion to provide about 10% in excess of the expected daily intake for ad libitum consumption. The control group was fed TMR containing about 10% high microbiologically quality corn silage (normal silage) + mycotoxindeactivator (MD) product, while the second group was fed TMR containing about 10% low microbiologically quality corn silage (naturally contaminated with mycotoxins) + MD product. A significantly (P<0.05) reduction in ruminal viable total bacteria and cellulytic bacteria count were observed in the group fed mycotoxin contaminated silage compared to the control group. Acetate and propionate concentration were significantly (P <0.05) lower in ruminal fluid of the cows fed mycotoxin contaminated silage than those in control group. Feeding mycotoxin contaminated silage significantly (P<0.05) decreased DM, CF, NFC and ADF digestibility compared to control group. While insignificant (P>0.05) differences were observed in digestibility of OM, CP, EE and NDF. No significant effect on the concentration of total protein, globulin, A/G ratio, bilirubin concentration and ALT and AST activity. Cows fed contaminated corn silage showed a decrease in the averagefeed intake andmilk production. Feeding contaminated corn silage resulted inincreased aflatoxin M₁ in milk. These results support that the hygienic quality of silage is more important than using mycotoxins deactivator for animal performance, even with using low percent of contaminated feed and maintain the level of total aflatoxin and aflatoxin B₁ concentration lower than the permissible limits.