Abstract: 【Objective】 This experiment aims to study the effects of intramuscular injection of compound polysaccharides on immune organs, blood routine indexes and the GM-CSF, G-CSF mass fraction in different MHC B-Lβ II genotype of laying hens.【Method】500 chickens were divided into three groups according to different genotypes by PCR-SSCP method. The genotypes were divided into high, medium and low dose Chinese herbal compound polysaccharide group and blank control group. Each group of the testing chickens were intramuscularly injected with 50 mg / mL, 25 mg / mL, 12.5 mg / mL Chinese herbal compound polysaccharide and saline, 0.2 mL / day for 7 days. At the age of 21, 35 and 49 days, 5 chickens were randomly selected from each group to measure the thymus, spleen and bursa of Fabricius viscera index, and blood samples were collected to measure the blood routine indexes and the changes of granulocyte colony stimulating factor G-CSF and granulocyte macrophage colony stimulating factor GM-CSF.【Result】The high, medium and low dose polysaccharides had certain effects on immune organs, blood routine indexes and GM-CSF in different genotype chickens, but the effects of different dosage polysaccharides on the same index of different genotypes were different. Among them, the high and medium doses of traditional Chinese medicine compound polysaccharide could significantly improve the organ index of thymus, spleen and bursa of fabricius in AA genotype chickens, and low dose of traditional Chinese medicine compound polysaccharide could significantly improve the total number of white blood cells and lymphocytes. In the BB genotype chickens, the high and medium dose of traditional Chinese medicine compound polysaccharide could significantly improve the thymus and spleen index, but had no effect on blood routine indexes. In the BC genotype chickens, high dose of traditional Chinese medicine compound polysaccharide could significantly improve the thymus index, white blood cell count and lymphocyte count, and the medium dose of traditional Chinese medicine compound polysaccharide could significantly improve the total white blood cell count and lymphocyte count.【Conclusion】Different doses of traditional Chinese medicine compound polysaccharide can improve the immune organ index, some blood routine index and GM-CSF mass concentration of hens in different genotype groups, and in general, the immune effect of Chinese herbal compound polysaccharide with high and medium doses is better.