Abstract: In order to observe the changes of immune function in KM mice before and after biocleaning,immunological examinations were conducted. The function of antibody formation cells was 557.39±85.7 and 368. 62±65.23，the antibody level in serum was 67.8±26.08 and 46.4± 15.45，the function of removing carbonaceous granule index K was 5.24 ± 0.96 and 4.61±0.61，a was 0.0032±0.0023 and 0.0025±0.001，the phagocytic function of macrophages in mice’s abdominal cavities 0.41±0.66 and 0.36±0.06，the mice’s lymphocyte transformation induced by ConA （OD value） 0.023±0.02 and 0.031±0.001 ,the mice’s DTH induced by DNFB 10.85±4.34 and 16.29±4.21 before and after biocleaning respectively. It was suggested that some of examined immune function changed significantly after bioclcaning such as the phagocytic activity, B lymphatic cells activity and antibody levels. However, no changes were observed in mice’s lymphocyte transformation induced by ConA.