The protein tyrosine phosphatase non-receptor 22 (PTPN22) 1858 C>T poly-morphic variant gene (rs2476601) displays an association with systemic lupus erythematosus (SLE) and other autoimmune diseases. However, its contribution to SLE has been found to be disputable. We therefore examined the association of PTPN22 1858 C>T polymorphism with susceptibility to SLE in the Polish population, among patients with SLE (n=150) and controls (n=300). We found a contribution of the PTPN22 1858 C>T polymorphism to the incidence of SLE. Women with the PTPN22 TT and PTPN22 CT genotypes displayed a 2.016-fold increased risk of SLE (95% CI=1.324 - 3.070, P=0.0014). However, we did not observe an increased risk for the homozygous PTPN22 TT genotype OR= 2.552 (95% CI=0.6748-9.64, p=0.1675). Our results confirm an association of the 1858 C>T polymorphism of the PTPN22 gene with SLE, which was previously observed in other populations.