Recently, associations were found between autoimmune diseases and variants of interleukin-23 receptor (IL23R) gene; here, we analyzed the association of nine IL23R polymorphisms with psoriasis and with immunoglobulin A nephropathy (IgAN). Groups of patients with psoriasis, IgAN, and controls were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. We observed a significant increase in the carriage of the minor allele of rs11805303 in psoriasis patients compared to controls. Similarly, for rs2201841 prevalence of the CC genotype and for rs10889677, the AA genotype showed a more than two- and threefold increase, respectively in patients compared to controls. There was no difference in the distribution of IL23R variants between controls and IgAN patients. We confirmed the association of IL23R with psoriasis in a Hungarian population and demonstrated the effect of the rs11805303 SNP, which was tested so far only for other autoimmune diseases. We could not detect any association between the IL23R variants and IgAN.