ObjectiveTo study the amplification and expression of HER-2 gene and protein in breast cancer and to investigate the relationship between HER-2 gene and Ki-67 、P53 、ER、PR、lymph node metastasisandTNMstaging.MethodsFluorescenceinsituhybridization(FISH) and immunohistochemistry(IHC) method were used to detect the amplification and expression of HER-2 and the expression of Ki-67、P53、ER、PR in 150 cases of breast cancer. Results49 out of 150 cases were amplificated,positive rate of HER-2 gene was 32.68％.In the 32 patients whose expression of HER-2 protein was ( + + + ),HER-2 gene was expressed in 28 cases.In The 46 patients whose expression of HER-2 protein was ( + + ),HER-2 was expressed in 16 cases.In the 26 patients whose expression of HER-2 protein was ( + ),HER-2 was expressed in 3 cases.In the 47 cases that the expression of HER-2 protein was negative,there were 45 cases that the expression HER-2 gene was negative.The expression of HER-2 was correlated with ER,PR expression and TNM staging,but not significantly related with age,Ki-67,P53 and lymph node metastasis.ConclusionsFISH and IHC correlate well with each other in the determination of HER-2 gene amplication and protein expression in cases of invasive breast cancer.