A method of analysis of the distribution of concentration of a substrate including: a step of preparing a plurality of types of sample substrates whose distribution of concentration is to be analyzed; a step of forming on the surfaces of those substrates dummy films of a material different from the substrates or etching the surfaces of the plurality of sample substrates to different depths; in the case of the dummy films; a step of introducing into the sample substrates specific impurities from the direction of the dummy films under substantially identical conditions and then a step of removing the dummy films; a step of performing mass analysis from the sides of the sample substrates; and a step of sequentially calculating the difference in the results of the mass analysis among the sample substrates.