There is disclosed a correlating operation method and a matched filter in which sensitivities in received code sequence selection and path detection are held to some degrees while circuit scale can be reduced. In the correlating operation method and the matched filter, code data obtained by adding or subtracting an in-phase component and a quadrature component of a received code sequence in a code mapping unit, and an in-phase component and a quadrature component of a received complex signal are subjected to correlating operation, and a correlating operation result is subjected to power adding operation to obtain a correlating operation output.