The aim of this study was the validation of the German translation of the ASAS Health Index (ASAS HI), which measures functioning and health in patients with axial and peripheral spondyloarthritis (SpA).Patients with SpA who fulfilled the ASAS classification criteria for axial (axSpA) or peripheral SpA (pSpA) were included in this study. Constuct validity of the ASAS HI was tested by using Spearman's correlation coefficients. Reliability was analyzed by intraclass correlation coefficients (ICC) in patients with stable disease. In patients requiring an important therapeutic change because of unacceptable high disease activity, the sensitivity to change was analyzed using standardized response mean (SRM).A total of 171 patients (57.9% male, age 44.4 ± 13.0 years) were included. The internal consistency was high with a Cronbach's alpha of 0.83. The reliability (n = 63) was good (ICC = 0.94; 95% confidence interval [CI] 0.90-0.96). The sensitivity to change of the ASAS HI was low for a relatively small number of cases (n = 33) with a SRM of -0.27 but showed a good ability to discriminate between various stages of disease activity and physical functioning.We showed that the German translation of the ASAS HI provide good psychometric properties to assess functioning and health in patients with SpA. This reliable and sensitive to change questionnaire therefore enables the assessment of disease-specific global functioning and severity in patients with all forms of SpA.