Abstract: A water filter has a filter body, a filtering tube and an assembling cover. The engaging portion of the filtering tube securely engages with the water channel of the assembling cover, and the engaging disk of the filtering tube securely engages with the engaging circular rib of the filtering space, such that the filtering tube is securely limited and positioned between the filter body and the assembling cover; furthermore, the filtering tube, the filter body and the assembling cover respectively engage with each other and are combined together by the welding process, to completely prevent the filtering tube from deforming and misplacing.