An electrode device for an electrochemical sensor chip includes an insulation sheet having an insulating property and including a top surface and a bottom surface opposite to each other in a thickness direction, and electrode members having a conductivity and held by the insulation sheet with the electrode members piercing the insulation sheet in a thickness direction, one ends of the electrode members located on the top surface side of the insulation sheet being connected to an analyte, the other ends located on the bottom surface side of the insulation sheet being connected to an electrodes of a transducer.