Abstract: This study deals with an experimental study on the effect of column cross section to frame ductility in RC frames. 2-bay, 2 story, 1/3 scale reinforced concrete frame specimens which were designed and constructed with deficiencies as observed in practice of Turkey were tested under reversed-cyclic lateral loading and low level axial loading. The difference between two specimens is column cross section area. The behaviour characteristics obtained from specimens at the end of the tests are determined; in addition, considering parameters like system ductility, strength and stiffness. In the analytical part of this study, pushover analyses were performed for two frame specimens. The results of tests and pushover analysis are compared between each other and evaluated. It is concluded that frame lateral ductility is related with column cross section.