Abstract: A filter element structure 100 attached to a backwash type filter W and filtering fluid flowing within the filter includes a pair of one and the other filter elements 10, and a connection pipe 13 connecting the one filter element 10 and the other filter element 10. Each of the filter elements 10 includes a filter medium 11 formed into a hollow cylindrical shape having open ends on both sides, an upper cover 12 covering the upper end of the filter medium 11, and an upper hole 12a penetrating the upper cover 12. One end of the connection pipe 13 is connected with the one upper hole 12a, while the other end of the connection pipe 13 is connected with the other upper hole 12a.