Abstract: This paper investigates the in-plane inelastic stability and ultimate strength of two-hinged steel circular arch subjected to hydrostatic pressure using large deformation elastic-plastic finite element method. Material inelasticity, residual stress, and initial geometric crookedness are considered in the investigation. Stability design curves of two-hinged circular steel arch with welded I-sections, rolled circular tubes and welded box sections are obtained from numerical analysis, and they are compared with the stability curves recommended by the German Standards and the American Structure Stability Research Council. The proposed curves can be used for practical design of two-hinged circular arches in uniform compression.