A two-storey reinforced concrete (RC) frame structure was designed and built in the coastal area of Qingdao, China. The RC fame has been exposed in a marine atmospheric environment for 14 years and steel reinforcements have noticeably corroded. With recourse to routine monitoring and inspection methods, the current states of the RC frame were assessed, including corrosion degrees/cracks, concrete strength, existing deformations/displacements, etc. Based on the measured current information, the mechanical properties of the corroded RC frame were calculated and evaluated according to current codes for appraisal of existing RC structures. However, usually the accuracy of the appraisal results is hard to be examined directly. Hence, a pushover test was designed and conducted on-site on the corroded RC frame to investigate the mechanical behavior and to examine the appraisal results. The vertical forces were exerted by concrete blocks putting on the floors. The lateral forces were exerted by actuators connected to a reaction frame. During tests, the lateral forces, lateral and vertical displacements, and strains in some specific points were monitored and recorded. The pre-evaluated results were compared with the test results to examine the validity of current methods for appraisal of existing concrete structures.