A retractable safety syringe comprises a needle body, a syringe barrel, and a pusher plunger. The needle body has a needle and a needle seat having an upper needle seat and a lower needle seat the upper needle seat is used for fixing the needle thereon and is provided with a connecting portion on the bottom and the removable lower needle seat can be embedded to the upper needle seat from below. The pusher plunger has a piston in the front end thereof the piston has a connecting member, which can connect to the connecting portion on the bottom of the upper needle seat, so that after injection, by applying a force to press and deform the piston till connecting to the connecting portion, the needle body can depart from the needle socket and the abutment and can be drawn back to the interior of the syringe barrel.
