Laser ignition has been receiving special interests recently because of the requirement of alternative strong ignition systems for internal combustion engine in next generation. The merits of the laser ignition over the conventional spark ignition are absence of wall or electrodes which quench an initial frame kernel, capability of multi-point ignition through single hole and characteristics that favors higher pressure. This third feature is noteworthy especially for recent supercharged engines. Recent development of new laser devices such as ceramics laser and VCSEL are also very important progress for the laser ignition. In this paper, laser ignition studies from fundamental to recent activity were introduced.