It is an object to provide a laser module in which the position and the posture of a laser beam source can be adjusted even in a small space so that an optical intensity necessary for recording and reproducing information can be ensured and the laser module is seldom affected by an ambient temperature. It is another object of the present invention to provide an optical pickup device, an optical disk device, a focus error detection method and a tracking error detection method. The laser beam source adjustment member 55 and the laser beam source shift member 56 are attached to the laser beam source 52 so that the lead 51 can penetrate them. Further, FPC 57 is fixed to the lead 51 being soldered. The laser beam source 52 and the laser beam source adjustment member 55 are fixed between the holding plate 54 and the laser beam source shift member 56 being pushed by the pushing spring 53. The laser beam source adjustment member 55 has a spherical face formed round a light emitting point of the laser beam source 52 and is rotated round the light emitting point of the laser beam source 52 so that an inclination of the laser beam source 52 with respect to the axial direction can be adjusted.