We observed significant association between HER2 Ile655Val polymorphism and breast cancer risk under the dominant (OR = 2.52; 95% CI: 1.41–4.51; p-0.001) and codominant (OR, 2.24; 95% CI: 1.23–4.09; p-0.008) model. The gene discussed is ERBB2; the disease is breast cancer.