A syringe assembly includes: a syringe including: a puncture needle having a needle tip, and a barrel holding the puncture needle； a hollow cylindrical grip fitted on an outer peripheral portion of the barrel； and a protective device including a hollow cylindrical cover member that is axially displaceable relative to the barrel, the protective device being configured such that the cover member covers at least part of the puncture needle in an initial state, the cover member is displaceable in a proximal direction relative to the barrel by being pressed against an object to be punctured when the puncture needle is inserted into the object to be punctured, and the cover member is configured to cover the needle tip after insertion of the puncture needle into the object to be punctured.
