The invention provides a manufacturing method of dynamic pressure bearing, which comprises the following steps: an obturator is provided, the surface of the obturator is convexly provided with a plurality of protrusions; the obturator is arranged in the central position of a hollow bearing mould, and a hollow cavity in the bearing mould is filled with the mode of encapsulation molding to form an embryo of the dynamic pressure bearing; the obturator is removed from the embryo of the dynamic pressure bearing through the mode of catalytically degreasing; binder in the embryo of the dynamic pressure bearing is removed; the embryo of the dynamic pressure bearing is sintered; finally, the dynamic pressure bearing is formed. The dynamic pressure bearing integrally forms the dynamic pressure bearing and a dynamic pressure groove through the method of encapsulation molding, and removes micro-molecular gases which is decomposed from the obturator by using the method of catalytically degreasing, thereby preventing the embryo of dynamic pressure bearing from generating defects as deformation, bending or fracture, etc., improving the mass production capability and the dimensional precision of the dynamic pressure bearing. The invention also provides a manufacturing method of a dynamic pressure rotating shaft.