This invention provides a sequence generating method, in which the method has steps of generating R sets of orthogonal sequence with each set of the orthogonal sequence including N elements, generating a low-autocorrelation sequence having N elements, and multiplying the N elements of the low-autocorrelation sequence by the N elements of each of R sets of the orthogonal sequence point-to-point. Therefore, a sequence generated by the method of the present invention has low-autocorrelation and low-crosscorrelation in transmission characteristics of a communication system.