In order to achieve a method for analyzing the compositional distribution of deposited film adhering to the internal surface of a contact hole having a diameter in the deep submicron order, primary ions 18 are radiated into the surface 12a of an insulating film 12 where the contact hole 14 is formed to generate secondary ions 20. The primary ions are radiated into the surface of the insulating film from a constant diagonal direction. Then, mass spectrometry is performed on the resulting secondary ions to detect the compositional distribution of the deposited film 16 formed at the internal surface of the contact hole. Thus, the compositional distribution of the deposited film is ascertained over the depth-wise direction of the contact hole.