The present invention provides a quantitative measurement method and quantitative measurement chip which can perform quantitative measurement of a target substance in a short period of time. The invention provides a quantitative measurement method in which a three dimensional mesh structure material is formed, and quantitative measurements are taken of the target substance using a structure which contains a reagent that reacts with the target substance in the mesh. This method includes a contacting step in which a test specimen which includes the target substance is brought into contact with the structure; a detecting step which, in a process in which a substance whose quantity will increase or decrease by means of the reaction between the target substance and the reagent, detects the substance whose quantity is increasing or decreasing within the structure at a contact interface between the test specimen and the reagent; and a quantitative measurement step which performs quantitative measurement of the target substance based on the results of the detecting step. The mesh structure will allow at least the target substance to pass therethrough.