Abstract:To evaluate the effect of sulfur-free complexed color-protecting agent against cold injury，using honey peach as experiment materials，and using untreated honey peach and 1-methylcyclopropene（1-MCP）treated honey peach as negative and positive controls，the effect of sulfur-free complexed color-protecting agent on physiology-biochemical indexs in peaches during cold storage was investigated.Results showed that，compared with untreated control，decay rate，browning index，respiratory rate，ethylene releasing rate，relative conductivity，polygalacturonase（PG）and cellulases（CX）activities in sulfur-free complexed color-protecting agent treated peaches were significantly reduced，while hardness，titratable acidity and soluble solids contents were significantly increased.From some tested indexs，the inhibiting effect of sulfur-free complexed colorprotecting agent against cold injury was even better than 1-MCP.Results indicated that sulfur-free complexed color-protecting agent preserved the integrity of the cell wall of the fruits by regulating respiratory rate and de－creasing ethylene releasing rate.These were useful to alleviate peaches cold injury and prolong storage.