Abstract: Two new methods of constructing low correlation zone(LCZ) sequence pairs set are proposed.One way to construct the LCZ sequence pairs set is to extend a long LCZ sequence generated with interleaved technique based on binary sequence with two-level periodic autocorrelation and orthogonal matrix pair.Another is to extend a long LCZ sequence pair generated with interleaved technique based on binary sequence pair with two-level periodic autocorrelation and orthogonal matrix pair.The construction methods are theoretically proved and some examples are given.They can give more choices for practical engineering because the existence domain of LCZ sequence pairs is wider.