The present invention realizes a puncture device and a medical fluid application device that can enhance the usability. A base (4C) that acts as a guide when sliding a center part (4D) including an outer needle (50) is arranged, where when a dial (5A) is rotated by a user, the base (4C) is rotated with respect to a fixed part (4B) to adjust the puncture angle. Thus, the puncture angle can be freely adjusted according to the physique, the subcutaneous thickness, and the like of the user, so that the effect of the medical fluid to be applied can be fully exerted and the usability can be enhanced.
