The present disclosure relates to measuring biosignals (particularly, electroencephalogram) of fish in a non-invasive and multi-channels manner, with a multi-channel electrode array of one or more conductive plates non-invasively attached to the epidermis of the fish outside of the water a a reference electrode non-invasively attached to the epidermis of the fish outside of the surface of the water a supply device that supplies a predetermined material and oxygen to the fish outside of the water and a minute tube inserted into the oral cavity of the fish outside of the water to resuscitate the fish in a stable state to generate normal electroencephalogram.
