The present invention provides a method for examining a foreign matter derived from a living body in quality control for production of various products in order to rapidly identify an individual from whom a living body-derived material contaminated as a foreign matter in products or facilities involved in production of the products was derived, while securing the secret of information on nucleic acid sequences unique to individuals. The method for examining a foreign matter derived from a living body includes identifying an individual from whom a living body-derived material contaminated as a foreign matter in products or facilities involved in production of the products was derived, on the basis of information on sequences of nucleic acid contained in the living body-derived material.