The objective of this study is to investigate the progressive collapse potential of reinforced concrete moment frames subjected to sudden loss of a first-storey column. To this end three-, six- and 15-story reinforced concrete moment frames were designed as model structures for analysis with and without considering seismic load, and their progressive collapse potentials were investigated by performing non-linear static and dynamic analyses. It was observed from the analysis results that the catenary action is activated by reinforcing steel and is proportional to the amount of the reinforcement. It was also observed that the amount of stirrup affects the onset of the catenary action and the progressive collapse. According to the non-linear dynamic analysis results the reinforced concrete structures that were not designed for seismic load turned out to be highly vulnerable to progressive collapse, whereas the structures designed considering seismic load showed superior performance against progressive collapse.