To provide a test tool for use in immunochromatography, by which a material to be measured in a liquid sample can be measured with accuracy and high sensitivity.

This test tool includes a first part 3 held in such a way that it can be moved by the capillary phenomenon and containing a first antibody specific to a material to be measured which is coupled to either avidin or biotin; a second part 4 labeled by a marker from which a visually detectable signal can be obtained and containing a substance that can form an avidin-biotin complex together with the avidin or biotin coupled to the first antibody; and a third part 5 having a portion which is specific to the material to be measured and in which a second antibody different in recognizable part from the first antibody is fixed. The first and second parts, and the second and third parts, are interconnected so that the capillary phenomenon occurs between them.