A self-destroying disposable syringe, comprising: a barrel having a hub on the front end of the barrel and a flange on the inner wall of the hub; a needle base connected to the hub of the barrel, the needle base comprising a connecting portion, a containing portion disposed on the outer side of the connecting portion, and a self-destroying ring disposed on the back end of the needle base and connected to the connecting portion through one or more ribs, said one or more ribs being breakable, the self-destroying ring is provided with an axial opening; when the needle base is connected to the barrel, the connecting portion and the self-destroying ring are located in the inside of the hub of the barrel, and the self-destroying ring matches the flange of the barrel; a plunger movably inserted into the barrel and comprising a bar body, a pushing stem connected to the back end of the bar body, a pushing disc connected to the front end of the bar body, and a puncturing portion, said puncturing portion being designed for puncturing through said self-destroying ring after injection for breaking said one or more ribs; a piston connected to the cone of the plunger, a cavity for containing the puncturing portion being provided within the piston, a sealed front wall being provided on the front end of the piston, an opening communicated with the cavity being provided on the back end of the piston; characterized in that, the plunger further comprises a cone with one end fixed to the pushing disc and the other end fixed to the puncturing portion, wherein the plunger is provided with a vent groove extending through the puncturing portion, the cone and the pushing disc. a barrel having a hub on the front end of the barrel and a flange on the inner wall of the hub; a needle base connected to the hub of the barrel, the needle base comprising a connecting portion, a containing portion disposed on the outer side of the connecting portion, and a self-destroying ring disposed on the back end of the needle base and connected to the connecting portion through one or more ribs, said one or more ribs being breakable, the self-destroying ring is provided with an axial opening; when the needle base is connected to the barrel, the connecting portion and the self-destroying ring are located in the inside of the hub of the barrel, and the self-destroying ring matches the flange of the barrel; a plunger movably inserted into the barrel and comprising a bar body, a pushing stem connected to the back end of the bar body, a pushing disc connected to the front end of the bar body, and a puncturing portion, said puncturing portion being designed for puncturing through said self-destroying ring after injection for breaking said one or more ribs; a piston connected to the cone of the plunger, a cavity for containing the puncturing portion being provided within the piston, a sealed front wall being provided on the front end of the piston, an opening communicated with the cavity being provided on the back end of the piston; characterized in that, the plunger further comprises a cone with one end fixed to the pushing disc and the other end fixed to the puncturing portion, wherein the plunger is provided with a vent groove extending through the puncturing portion, the cone and the pushing disc.