Effects of 2 various levels of AME (according to the manual recommendation and 100 kcal kg(-1) less than it), 2 levels of endo-beta-D-mannanase enzyme (0, 1 g kg(-1)) and 2 levels of xylanase enzyme (0 and 1 g kg(-1)) on serum lipid parameters as a 2(3) factorial arrangement were tested in 120 male broiler chicks fed wheat-soybean meal-based diet. These birds were randomly assigned to 8 experimental groups with 3 pen per group and 5 birds per pen. The serum HDL-cholesterol (HDL), LDL-cholesterol (LDL), Total-cholesterol (TC) and Triglycerides (TG) concentrations were measured at 31 and 41 day of age. The concentrations of serum TG, TC and LDL of 41-day-old birds demonstrated to be lower than those of 31-d-old (p < 0.001). Some hypolipidemic responses were observed in the broiler chicks fed on (1) Diet supplemented with only beta-mannanase, (2) Normal-AME diets supplemented with p-mannanase, (3) Normal-AME diets supplemented with Xylanse and (4) Normal-AME diets supplemented with both beta-mannanase and Xylanase (p < 0.01). In the other hand, some hyperlipidemic responses were detected in the broiler chicks fed on low-AME diets supplemented with xylanse or beta-mannanase enzymes, alone or in combination (p < 0.01). Regardless of AME, adding both xylanse and beta-mannanase to the wheat-soybean meal-based diets have both hyperlipidemic and hypolipidemic effects together (p < 0.01).