Abstract: Mirror carp surimi sausage was fermented using Pediococcus pentosaceus and the effect of fermentation time on quality properties which included pH, TA, color and relaxation time and gel properties were investigated to determine the optimized fermentation condition: ferment at 25 ℃ for 48 h. In this condition, carp surimi sausage formed compact fibrous network with higher gel strength ( 972.73 g × cm) , which lead to a superior sensory quality. Meanwhile the ratio of hydrogen bonds, ionic bonds in mirror carp surimi sausage decreased significantly ( p < 0.05) from 34.47% and 22.26% to 8.67% and4.19%. Gel strength and hydrophobic interactions, disulphide bonds and non-disulphide were increased during fermentation under this condition as well.The content of disulfide bonds increased significantly from the initial 5.93 μmol/g to 11.93 μmol/g ( p < 0.05) . Results showed that gelation of fermented surimi was mainly caused by organic aeids produced during fermentation, hydrophobic interactions, disulphide bonds and non-disulphide covalent bonds were mainly responsible for the formation of gel network of fermented mirror carp surimi sausage, and hydrophobic interactions were particularly important during the initial stage of gel forming. Extensive formation of disulphide bonds and non-disulphide covalent bonds occurred during the later stage of fermentation, intensifying the gel network.