Provided according to the present invention are a puncture device and a chemical liquid supplying device capable of considerably reducing a burden imposed on a user. When a push-in unit 5A is pushed in, an outer needle 65 containing an inner needle 68 inside is inserted into the body of a user in accordance with downward sliding of a center unit 5D of a puncture mechanism 5. When the push-in unit 5A is completely pushed in, stopper levers 72A and 72B of the center unit 5D open and return only an outer needle slide unit 66 of the center unit 5D to the original position by the restoring force of a coil spring 85. This retracts only the outer needle 65 into a chemical liquid supplying device 1 with the inner needle 68 indwelled within the body of the user. In this case, the indwelled needle is the inner needle 68, wherefore the diameter of the indwelled needle is easily made smaller in comparison with a conventional puncture needle whose indwelled needle is the outer needle 65. Accordingly, a burden imposed on the user can decrease.
