Abstract: An apparatus which can confine almost entire available energy in the vicinity of ignition point during a laser-induced ignition process is proposed. Multiple reflection by a cavity surface when a small diameter laser beam is directed into the cavity is utilized in laser ignition. Shadowgraphs of the early stages of the combustion process for quiescent methane/air mixtures show that a hot gas jet emerges from the cavity. During subsequent flame propagation, both similarities with and difference from conventional spark ignition processes are observed, depending on the cavity size and the concentration of mixtures. With laser cavity ignition, the chamber pressure increases relatively rapidly and higher maximum pressure can be achieved. As a result, the combustion duration for laser cavity ignition is decreased relative to laser-induced spark ignition.