A device for electrical measurement of a target chemical substance, comprising: one or more electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) each including a base , an electrode array section in which one or more electrodes which are disposed on the base and to each of which a test substance having a bonding property to a target chemical substance is fixed or can be fixed are arrayed, and a terminal array section in which one or more terminals disposed on the base so as to correspond to the electrodes and electrically connected to the electrodes are arrayed; a processing head including one or more electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) supporting the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) detachably to make electrical connection to the terminals possible; a container group including one or more liquid storing sections storing or capable of storing liquid, and one or more measurement containers ; a support section moving mechanism capable of relatively moving the one or more electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) with respect to the container group ; and a measurement section capable of measuring a signal generated by applying a predetermined voltage to a test substance fixed to each of the electrodes in the measurement containers , wherein the container group includes one or more electrode array element storing sections storing or capable of storing the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) such that the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) can be supported by the electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) due to the support section moving mechanism . one or more electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) each including a base , an electrode array section in which one or more electrodes which are disposed on the base and to each of which a test substance having a bonding property to a target chemical substance is fixed or can be fixed are arrayed, and a terminal array section in which one or more terminals disposed on the base so as to correspond to the electrodes and electrically connected to the electrodes are arrayed; a processing head including one or more electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) supporting the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) detachably to make electrical connection to the terminals possible; a container group including one or more liquid storing sections storing or capable of storing liquid, and one or more measurement containers ; a support section moving mechanism capable of relatively moving the one or more electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) with respect to the container group ; and a measurement section capable of measuring a signal generated by applying a predetermined voltage to a test substance fixed to each of the electrodes in the measurement containers , wherein the container group includes one or more electrode array element storing sections storing or capable of storing the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) such that the electrode array elements (2 1 -2n, 21 1 -21 4 , 22 1 -22 4 , 23 1 -23 4 ) can be supported by the electrode array element support sections (4 1- 4 n , 41 1 -41 4 , 42 1 -42 4 , 43 1 -43 4 ) due to the support section moving mechanism . <EOS>