The invention discloses a fully automatic assembling machine for a blood sampling needle. It includes an index plate, an indexer, a front spring assembly workpiece and a rear spring assembly workpiece, and the needle core is rotated to the front spring assembly workpiece and the rear spring assembly by the rotation of the index plate For the work position of the workpiece, the first vibrating plate leads out the front spring parts in an orderly manner. The first disperser ensures that only one front spring part enters the first discharge pipe at a time. The first discharge pipe makes the front spring parts arranged in an orderly manner, and It can be installed on the upper end of the needle core in succession; the second vibrating plate leads out the front spring parts in an orderly manner, the second disperser pushes the rear spring parts to the second discharge tube one by one, and the rear spring parts are sleeved on the needle core of the blood sampling needle After the lower end, by rotating the indexing plate, the rear spring part is moved out of the gap of the discharge interface with the needle core of the lancet. Accurate installation makes the structure of the entire lancet fully automatic assembly machine more compact.