This experiment mainly describes the effects of acupuncture on immunologic function and histopathology of transplanted mammary cancer in mice. The results were as follows: In acupuncture group

NK cell activity and T-lymphocyte positive rate of acid α-naphthyl acetate esterase (ANAE) and lymphocyte transformation rate were all increased. Compared with the control group

there was a significant difference (P<0.01). The difference was insignificant when compared with normal group (P>0.05). Comparing the pathology grading of acupuncture group with control group

it showed marked difference in pathological section (P<0.01). Adenoid structure and the degree of lymphocytic infiltration also have marked difference between acupuncture and control group (P< 0.05). Less tumour volume in acupuncture group than in control group were observed (P<0.01). This indicated that acupuncture might increase the immunologic function of transplanted mammary cancer in mice and inhibit the growth of mammary cancer and enhance both differentiation level of mammary cancer cells and lymphocytic infiltration. Possibly acupuncture might reduce the malignancy of mammary cancer cells.