A biological signal acquisition device includes an electrode made up of a plurality of cell electrodes, and a controller that acquires an electrical signal from a biological body through a pair of cell electrode groups made up of a part or all of the plurality of cell electrodes. The controller determines a contact condition between the part or all of the plurality of cell electrodes and the biological body, based on a detection signal acquired by scanning the part or all of the plurality of cell electrodes. Further, the controller selects the cell electrodes making up the pair of cell electrode groups, based on the determined contact condition so that contact resistances between the cell electrode groups and the biological body are equal between the pair of cell electrode groups.
