The expression levels of LAP3 in the serum of 40 breast cancer patients and 35 healthy people were detected by ELISA, and the results showed that the average concentration of LAP3 in the serum of breast cancer patients was 1.09 ± 0.43 ng/mL, which was higher than that in the serum of healthy control population (0.77 ± 0.33 ng/mL). This evidence concerns the gene LAP3 and breast carcinoma.