Abstract: Mango peel were fermented by Lactobacillus bulgaricus and Streptococcus thermophiles ( ratio 1 ∶ 1) to prepare mango peel dietary fiber ( MPDF) . Effect of inoculum sizee, fermentation temperature, fermentation time on yield of MPDF were investigated, and the fermentation conditions were optimized by single-factor experiments and orthogonal test. The results showed that the optimum conditions were 3% inoculation, fermentation temperature 38 ℃ and time 3 h. Under this condhions, the yield of MPDF was 31.74% with total dietary fiber content ( TDF) 68.00%.The water holding capacity, oil holding capacity and swelling capacity of the prepared MPDF were 11.19 g/g, 5.11 g/g and 1.07 m L/g, respectively. Compared with non-fermented mango peel, the purity and physicochemical properties of prepared MPDF were improved, which indicated that fermentation method was a feasible method for MPDF preparation.