Iron isotope ratios (delta Fe-56/54) of various anthropogenic materials produced by combustion processes were analyzed. It was revealed that particles emitted through combustion processes, such as fine aerosols collected from a tunnel or fly ash (extracted by 1.0 M HCl solution), yielded much lower isotope ratios than other materials on the earth's surface environment. These results suggest that the low delta Fe-56/54 was caused by human activities such as combustion processes.