The haplotype analysis showed that the Ars10204525 Trs2227982 Crs7421861 haplotype was associated with a significantly decreased risk of breast cancer (OR = 0.50, 95% CI = 0.34-0.75).Our findings support an association between the PD-1 rs2227982 polymorphism and decreased breast cancer risk, especially in Her-2 positive breast cancer patients in the Chinese population.