The effect of phenolic resin on laser ignition of B/KNO3 was studied by detecting the delay time of ignition of a composite, and by means of EMS and DSC as wel1. It was shown that the igniting delay time and the strength of the photoacoustic signal of B/KNO_3 with phenolic resin are smaller than those without phenolic resin at certain laser energy. Phenolic resin prevents the energy and the mass transfering to environment.According to the analysis of the ablated spots by EMS, the difference between B/KNO3 and B/KNO3/phenolic resin is small. A lot of ignition centers are formed at the surface of the composite by the incident laser.