Laser spark plug

The plug (1) has a fastening section (3) fastening a housing (2) in a cylinder head (11) of an internal combustion engine. A sealing seat (4) is viewingly spaced at a distance from the fastening section in an axial extension of the housing. A pressure sensor (5) is viewingly arranged between the sealing seat and the fastening section in the axial extension of the housing. The housing includes a section, which is designed as a sleeve (6) or is connected with another sleeve i.e. clamping sleeve, which is designed separate from the housing. The sensor is arranged at the sleeves.