BACKGROUND: Haptoglobin (Hp) is an acute-phase protein and an independent marker for hidradenitis suppurativa (HS) severity. The different Hp genotypes (Hp 1-1, Hp 1-2, and Hp 2-2) differ in their antioxidant and anti-inflammatory functions. Hp genotypes have never been investigated in HS patients. OBJECTIVE: Our aim was to characterize and determine the frequency of Hp genotypes in HS patients. Additionally, the characteristics of the different Hp genotypes are analyzed for differences in personal, disease-specific, and laboratory parameters. METHODS: Genomic DNA was extracted from peripheral blood leukocytes using the Maxwell RSC Blood DNA Kit. Polymerase chain reaction (PCR) products were separated and analyzed using 0.7% agarose gels for genotyping. The chi-square test, Kruskal-Wallis test, and/or post hoc analysis with the Dunn-Bonferroni test were used to determine differences between the different genotypes and HS characteristics. We compared the genotype distribution in HS with 69 randomly selected, unmatched, and healthy control patients. RESULTS: A total of 72 patients with HS were included in this study, including 29 women (40.3%) and 43 men (59.7%). A positive family history of HS was reported by 29.2% of patients (n = 21). Hp genotype 1-1 was present in 20.8%, Hp 1-2 in 33.3%, and Hp 2-2 in 45.8% of HS patients. The control group had a similar Hp distribution with 18.8%, 37.7%, and 43.5%, respectively. A positive family history of HS was significantly more frequent in Hp 2-2 (42.4%) compared to Hp 1-1 (6.7%) and Hp 1-2 (25%) (p = 0.035). The number of HS flares in the last 4 weeks was significantly higher in Hp 2-2 patients compared to Hp 1-2 patients (p = 0.006). CONCLUSION: Hp genotype 2-2 and the Hp2 allele were significantly more associated with familial HS than the other genotypes. In addition, HS patients with genotypes 2-2 had more frequent flare-ups than those with the different genotypes.