The present invention discloses an air dryer valve seat oblique hole processing intelligent fixture and a clamping method. The precise adjustment of the position obliquity of a hole to be processed is difficult to realize by an existing workpiece oblique hole fixture, and the position precision of the hole is difficult to ensure. According to the air dryer valve seat oblique hole processing intelligent fixture, the bottom of a workpiece clamp platform is provided with a rotation block which is in key connection with a warp direction rotation shaft, and two ends of the warp direction rotation shaft are supported on a belt bearing seat side plate through bearings. The output shaft of a warp direction rotation servo motor is fixed to the warp direction rotation shaft. Two weft direction rotation shafts are symmetrically fixed at two sides of the belt bearing seat side plate and are supported on a weft direction bearing seat through bearings. The output shaft of a weft direction servo motor is in key connection with one weft direction rotation shaft. A second horizontal axial movement platform drives a bottom plate, and a first horizontal axial movement platform drives the second horizontal axial movement platform. According to the air dryer valve seat oblique hole processing intelligent fixture and the clamping method, the linkage of two rotational degrees of freedom and two translational degrees of freedom is realized, and a valve seat position coordinate can be automatically identified.