A method for conducting a receptor-ligand association reaction includes the steps of dipping a biochemical analysis unit including a substrate formed with a plurality of absorptive regions which contain receptors or ligands and are formed to be spaced apart from each other in a reaction solution containing a ligand or receptor labeled with a labeling substance, simultaneously inserting a plurality of electrodes into all of the plurality of absorptive regions containing the receptors or ligands and sequentially applying a positive voltage to one of the electrodes at a time while other electrodes are grounded, thereby conducting a receptor-ligand association reaction. According to the this method, it is possible to efficiently react a ligand or receptor with receptors or ligands fixed in the plurality of absorptive regions of the biochemical analysis unit and produce biochemical analysis data having an excellent quantitative characteristic with good repeatability.