Three kinds of food antibacterial improver(sodium dehydroacetate,calcium propionate and ascorbic acid)were added into the formulas of steamed bread respectively to evaluate the quality of the steamed bread(using straight dough method)by preservation period,taste,appearance and flavor.The effects of antibacterial agents on the quality preservation and fresh-keeping of steamed bread.and the optimal bacteriostatic formula was studied.The results showed that the steamed bread can be produced with the best quality and the optimal bacteriostatic effect when the amount of antibacterial agents(mass fraction)were 0.015% sodium dehydroacetate,0.1% calcium propionate and 0.18% ascorbic acid.