Hidradenitis suppurativaHidradenitis suppurativa (HS) is an inflammatory skinSkin condition involving dysregulation of the innate and adaptive immune responses. Although the precise etiology is not yet elucidated, the pathophysiologyPathophysiology of HSHidradenitis suppurativa is multifactorial and associated with geneticGenetic and environment factors. There is currently no cure for HS. BiomarkersBiomarkers have been identified in the bloodBlood and tissueTissue of patients with the disease, and the levels of which may be informative about diagnosisDiagnosis, prognosis, treatmentTreatment efficacy, and monitoring comorbidities for this condition. These biomarkers encompass a wide range of molecules and include inflammatory cytokinesCytokines, chemokine receptorsCXC Chemokine Receptors, growth factors, markers of serum inflammation, and imaging features (Napolitano et al. in Clin Cosmet Investig Dermatol 10:105–115, 2017). Together, these biomarkers serve as important indicators of disease progression and response to treatmentTreatment. The World Health Organization (WHO) categorizes biomarkers into screening, diagnostic, prognostic, monitoring, and pharmacodynamics. The chapter will discuss the role of biomarkersBiomarkers in HS, focusing on diagnosis, prognosis, monitoring, and therapeutic targets.