Provided is a backside illuminated semiconductor light-receiving device enhancing a frequency characteristic without deteriorating assembling operability. The light-receiving device includes a rectangular substrate; a light receiving mesa portion formed on a center portion of one side on a front surface of the substrate and includes a PN junction portion; a P-type electrode formed on the light receiving mesa portion and conductive with one side of the PN junction portion; an N-type electrode mesa portion formed on one corner portion of the one side; an N-type electrode pulled out to the N-type electrode mesa portion and conductive with the other side of the PN junction portion; a P-type electrode mesa portion and a dummy electrode mesa portion formed in a region including three other corner portions; and a dummy electrode formed on the dummy electrode mesa portion.