The invention discloses a safe, energy-saving and environment-friendly dosing apparatus for oil extraction sewage treatment. In the apparatus, the middle of a medicament flow guide pipe I is providedwith an electric executive valve, the other end of the medicament flow guide pipe I communicates with the bottom of a liquid level balance tank, the bottom of the liquid level balance tank is connected with an inlet of a dosing pump through a medicament flow guide pipe II, an outlet of the dosing pump is connected with a dosing pipe, the dosing pipe is connected with a reaction pool through a lower tee, a "U"-shaped pipe and a dosing flowmeter, and thereby the impact of a liquid level height of a medicament storage tank on the dosing pump is reduced, when the system is not operated normally, amedicament cannot automatically flow into the reaction pool, the safety of the system is ensured, a gas discharge pipe is arranged on the top of the medicament storage tank, the gas discharge pipe communicates with the top of the liquid level balance tank through an upper tee and an upper communication pipe, the gas discharge pipe is connected with the lower tee at the upper part of the dosing pipe, the top end of the gas discharge pipe is connected with an orifice of a venturi pipe through an elbow, a sewage pipeline is connected with the upper end of the venturi pipe through a sewage flowmeter, and the lower end of the venturi pipe is connected with the reaction pool, so that the impact of medicament volatile gases on the environment is reduced, and energy is saved and environment is protected.