Magnetic quantum-dot cellular automata (MQCA) corner structure consists of both ferromagnetic coupling and anti-ferromagnetic coupling. Signal propagation of corner structure for magnetic material Fe is theoretically investigated by applying an external clocking field method. Magnetization evolution image on signal propagation of the corner is presented by micromagnetic simulation; it is shown that Fe nanomagnets can ensure stable switching of corner including two kinds of lengthy coupling. The proposed corner structure is then fabricated by electron beam lithography, thermal evaporation and lift-off technologies. Scanning electron microscopy and magnetic force microscopy measurement results demonstrate perfect pattern and correct signal propagation of two types of coupling.