The invention discloses a multiplex pulse ignition laser initiation system, and relates to the field of design of engineering civil initiation systems. The multiplex pulse ignition laser initiation system comprises an optical cable detection laser generator, n pulse initiation laser generators, n combiners, n first laser power meters, n optical splitters, n optical cable connectors, n laser initiating explosive devices, a light path selective switch, a second laser power meter, an A/D module and a controller; and n is a positive integer larger than or equal to 2, and each combiner, the corresponding first laser power meter, the corresponding optical splitter, the corresponding optical cable connector and the corresponding laser initiating explosive device form one optical cable passage, and n optical cable passages are jointly formed. The novel multiplex pulse ignition laser initiation system has the optical cable passage checking and environment temperature drift compensation capacity, the consistency of all single-way initiation lasers is improved, and the high safety, reliability and stability are shown In the civil initiation application process.