In this work, we investigate the effect of thickness ratio of Ti/Si constituent layer, bilayer thickness and total thickness on the self-propagating reaction behavior. It is presented that the Ti-Si multilayer films of Ti:Si = 1:2 show intensive self-propagating reaction. The films can react instantly by just applying mechanical shock. The multilayer films with the bilayer thickness of 〜25 nm appear to need the least energy to ignite the self-propagating reaction regardless of the Ti/Si thickness ratio.