An electrode assembly for a conductivity meter or resistivity meter includes: an electrode main body; a test liquid intake flow path passing through the electrode main body; a pair of voltage electrodes which is respectively provided so that surfaces thereof are exposed to opposing inner wall surfaces forming the test liquid intake flow path; and a pair of current electrodes which is respectively provided so that surfaces thereof are exposed to each of the inner wall surfaces, and in this configuration, each of the pair of current electrodes contains a carbon-based material, and each of the surfaces of the pair of current electrodes exposed to the inner wall surfaces is in a strip shape.