This paper presents out-of-plane behavior of circular arches subjected to lateral loads. The arches are analysed by dividing it in three components (two arch ribs and a lateral bracing system) and by solving the elastic differential equations for them with the aid of the Laplace transformation method. In relation to interaction of flexural rigidity of cross beam, torsional rigidity of arch ribs and warping rigidity as a whole cross section of the arch, the effect of biaxial flexural rigidity of individual arch ribs on their out-of-plane behavior is chiefly investigated. The effect of end-supporting conditions of the arches is also discussed.