Safety syringe with retractable standard needle including a syringe barrel, a plunger and an injection needle. A commonly used standard medical injection needle can be firmly fitted with the needle holder in accordance with the requirement of a user. The inner wall of the internal chamber at the open end of the syringe barrel is formed with an entrance recess extending along the axis of the internal chamber. The operating end of the plunger is formed with a radially outward projecting stopper section for preventing the needle pulling mechanism of the plunger from being accidentally latched with the needle pulling mechanism of the syringe barrel.