The invention discloses a self-sealing type bottle cap for an oil bottle. The seal-sealing type bottle cap for the oil bottle consists of a sealing cap, a one-way valve and a bottle cap body, wherein the sealing cap consists of a cap opening and a cap body; the cap body is in threaded connection with the bottle opening of the oil bottle; a sealing surface is arranged on the inner side of the cap opening; the one-way valve is arranged on the sealing cap and consists of a valve seat, a valve rod, a spring blocking cushion and a spring; one end of the valve rod is integrally connected with the valve seat; the other end of the valve rod is provided with the spring blocking cushion; the spring is arranged on the valve rod and is positioned by the spring blocking cushion; the valve seat is positioned at the cap opening of the sealing cap and is in plane contact with the sealing surface of the cap opening; and the bottle cap body is in threaded connection to the cap opening of the sealing cap. The self-sealing type bottle cap for the oil bottle has the advantages that oil in the oil bottle can flow out through the one-way valve, but air cannot enter the oil bottle from the bottle opening, so that edible oil in the bottle is isolated from the air, oxidation of the edible oil is stopped, the expiration date of the edible oil is prolonged, and the edible oil is safe to eat.