Abstract: The electrochemical analysis kit includes an electrode section, an immobilized conjugate (2), and a labeled conjugate (4). The electrode section includes a pair of electrodes: a working electrode (11) and a counter electrode (12), the immobilized conjugate (2) specifically binding to an analyte (3), and is immobilized at a specific site in a state of being bound to the analyte (3), the labeled conjugate (4) also binding to the analyte (3), and is labeled with a metal particle (4a), when the sample contains the analyte (3), both conjugates (2, 4) bind to the analyte (3), causing the labeled conjugate (4) to be immobilized at a specific site, the specific site enables the metal particle (4a) to undergo oxidation, followed by reduction via potential control of the working electrode (11), resulting current is measured through the electrodes pair, and at least one of the conjugates (2, 4) is an aptamer.