A safety syringe structure includes a plunger having two ends respectively forming first and second push sections. The first push section is provided with a cover that includes a peg extending therefrom. The peg has a distal end forming a retention element and is combinable with a connection member that has an opposite end forming a hollow tube. The connection member includes a constraint hole formed therein and in communication with the outside. The constraint hole includes a stepped section formed therein. The peg includes an elastic element fit thereto and is insertable into the constraint hole such that the retention element is in abutting engagement with the stepped section. A barrel that has an interior forming a receiving space has a top end face forming flanges extending therefrom and a bottom end face on which a hollow mounting section is mounted for receiving a needle mounted thereto.
