COMBUSTION PRESSURE DETECTION DEVICE, AND INTERNAL COMBUSTION ENGINE EQUIPPED WITH COMBUSTION PRESSURE DETECTION DEVICE

A combustion pressure detection device for detecting combustion pressure inside a combustion chamber of an internal combustion engine, the combustion pressure detection device being attachable to a communication hole 4a communicating an inside of a cylinder head 4 configuring the combustion chamber and an outside thereof, the combustion pressure detection device includes: a housing 30; and an piezoelectric element and the like that are located in the housing 30 and detect the combustion pressure. The housing 30 has an attachment structural part attachable to the communication hole 4a, the attachment structural part has a third outer peripheral surface 333 to which a first seal member 71 is attachable, and a inclined surface 315a to which a second seal member 72 is attachable, and the inclined surface 315a is arranged at a front end side in a direction to the combustion chamber relative to the third outer peripheral surface 333 when the combustion pressure detection device is attached to the communication hole 4a.