PURPOSE: To measure the amount of impurities sticking on the surface of a body to be measured with high sensitivity and high accuracy by driving the body to be measured and bringing a stick which is formed by cooling and solidifying a solution into contact with the surface of the body to be measured.

CONSTITUTION: A silicon semiconductor substrate 10 as the body to be measured is driven to rotate horizontally. The stick 11 formed by cooling and solidifying the solution which dissolves natural oxide containing impurities sticking on the surface of the substrate 10 in a rod shape is brought into contact with the surface of the substrate 1. This stick 11 is clamped by a chuck 12 and held so that its tip part contacts the surface of the substrate 10. Then the chuck 12 is so driven that the stick 11 moves in parallel from the output periphery of the substrate 10 to the center of rotation or in its opposite direction. Then the natural oxide on the surface of the substrate 10 is dissolved, its solution 13 is held and recovered, and the solution is analyzed by a chemical analyzing method which uses a spectroscopic analytic device to measure the amount and concentration of the impurities, thereby judging the extent of contamination of the substrate 10.