PURPOSE: To easily and certainly perform the flaw detection of a specimen having a complicated shape by simply removing the powdery adsorbent having adsorbed the liquid penetrant remaining on the surface of the specimen by using a brush or by sucking, by using an inorg. or org. powder adsorbing the liquid penetrant for a flaw detection test as a removing agent.

CONSTITUTION: A powder 6 (liquid penetrant removing agent) with a particle size of 5W20μm such as an inorg. powder such as an Al2O3 or SiO2 powder, starch such as wheat flour or an org. pigment powder is scattered on the liquid penetrant 2 for a flaw detection applied to the surface of a specimen 1. After the powder 6 adsorbed the excessive liquid penetrant 2 sufficiently, said powder 6 is removed by using a brush or by sucking. After removal, a developer 5 is sprayed to uniformly coat the surface of the specimen 1 to develop an aperture flaw 3. By this method, the aperture flaw 3 of the specimen 1 having a rough surface state or a complicated shape can be simply and certainly detected.