This study was to investigate the effect of chitosan-ascorbate (CA) prepared with different molecular weight (223, 746, 1110 and 2025 kDa) on the fermentation and quality of mul-kimchi, and also, the effect of the mul-kimchi juice fermented with 0.1% chitosan-ascorbate prepared with 2025 kDa chitosan (CA2025) on the serum lipids of rae fed with high cholesterol diet (HC). The mul-kimchi fermented in 0.1% CA2025 has lower turbidity, longer shelf-life, higher glucosamine content and SOD activity than those of control and the other treatments. In the animal experiment the HC-CA2025 and HC-2CA2025 groups which were administered 0.5 mL per 100 g body weight of mul-kimchi juice fermented with 0.1% CA2025 and administered the same volume of the juice concentrated 112 per nay fed for 5 week, respectively. The average body weight of the HC-CA2025 and HC-2CA2025 group was lower 6.9% and 8.4% than that of HC control group respectively. Total serum cholesterol contents of these groups were 88.33 and 85.00 mg/uL, which were 17.45% and 20.56% lower than HC control group respectively. While, HDL-cholesterol content of these groups were 7% and 23%, higher the LDL-cholesterol content were 13% and 26% lower than those of HC control group respectively. And also, though the atherogenic index, AST and ALT activities were not reached to normal control group, the values were remarkably lower than those of HC control group. This study indicates the possibility of utility for kimchi industry by adding chitosan-ascorbate, especially CA2025 showing not only quality enhancing and shelf-life prolongation but also improving serum lipids and atherogenic index in rats fed with high cholesterol diet.