A composite transmission housing for a vehicle drive train transmission is configured for sealingly enclosing transmission shafts, gearwheels, and a lubricant fluid within an internal space of the housing and includes: a first carbon-fibre skeleton part having a first attachment region; a second carbon-fibre skeleton part having a first attachment region; a first sealing cover part made of plastic material and having a first sealing surface; and a second sealing cover part made of plastic material and having a second sealing surface. The first attachment regions of the first and second carbon-fibre skeleton parts are mutually connected for providing a rigid structural framework that defines said internal space, and the first and second sealing surfaces of the first and second sealing cover parts are pressed together or against corresponding sealing surfaces associated with the first and second carbon-fibre skeleton parts, for providing a sealing envelope around said internal space.