In this paper, a new synthetic protocol for one-pot preparations of 5-halo-1,4-disubstituted-1,2,3-triazoles is provided by rational combination of a CuI catalyzed azide–alkyne cycloaddition (CuAAC) reaction and an oxidative halogenation reaction. CuI- N-chlorosuccinimide (NCS) and CuBr-NCS reaction systems are developed, respectively, for effective preparations of 5-iodo-1,4-disubstituted-1,2,3-triazoles and 5-bromo-1,4-disubstituted-1,2,3-trizoles under mild conditions with a high tolerance of various sensitive groups.