Semiconductor laser ignition system has not only been widely applied in safe and reliable ignition but also possesses obvious advantaged for anti-jamming in complex electromagnetic environment ，due to its small size, light mass and energy transmission by optical fiber. To investigate the ignition characteristics of laser igniter, a new type of semiconductor laser system and laser igniter filled with micron-sized B/KNO₃/PF were designed and prepared. TG-DSC, SEM, TEM, EDS, laser reflectance and Laser induced breakdown spectroscopy were used to study the thermal behavior, morphology, distribution of element, laser absorption efficiency, and emission spectra of B/KNO₃/PF. Then the ignition characteristics of B/KNO₃/PF igniter were studied by the semiconductor laser ignition system. The results showed that the initial reaction temperature of B/KNO₃/PF decreased and the heat release increased with the higher PF mass ratio and the smaller particle size in the DSC curve. The ignition process of the laser igniter can be divided into two stages: first ignition and secondary ignition. The pulse laser had a significant effect on the ignition characteristics of the igniter. The igniter could normally ignite with the 50% ignition energy of 6.23 mJ and 12.54 mJ, respectively, when the laser pulse were 5 ms and 10 ms. The first ignition delay time of 3.50-4.69 ms, secondary ignition delay time of 7.23-8.08 ms, and flame duration of 58-83.5 ms were produced in the laser igniter by changing the laser pulse and energy. The laser ignition system cannot motivate the igniter to fire normally when the laser pulse was 2 ms. These characteristics were consistent with the energy output law of semiconductor laser.