Abstract: A stem structure of a cleaning brush has a stem including a first segment having a threaded hole and at least two tabs all provided on the front end thereof, and a brush element including a body. Predetermined positions of the intermediate section of the body are provided with a through opening for receiving a threaded section of a fixing element and provided with at least two bores corresponding to the tabs. The threaded hole of the first segment of the stem is provided to screw with the threaded section of the fixing element, and the tabs of the first segment of the stem are inserted into the bores of the body. The fixing element is integrally made of plastic material.