The utility model provides a device for continuously reducing hydrogen sulfide in an oil well shaft. The device comprises a container body, wherein the inner part of the container body is a space for containing a treating agent; and a through hole is formed in the wall of the container body and is used as a channel by which crude oil flows in and out from the inner space of the container to be contacted with the treating agent for reaction. The device also comprises the solid treating agent contained in the container body. The device is connected under an oil well pump to be run into a well, the solid treating agent is put in the crude oil to be slowly dissolved to release needed alkali for reducing the hydrogen sulfide, and the alkali continuously reduces the hydrogen sulfide. The hydrogen sulfide in the crude oil can be eliminated before the crude oil is extracted from a wellhead, and the hazard of hydrogen sulfide is eliminated.