Along with the development of Bohai oilfield, deep wells, extended-reach wells and some other high difficulty wells operation are greatly increasing. It is an inevitable requirement to run liner into the well or land sand screen after well completion. But this operation is generally carried out in deep well section with great difficulty, reaming becomes the main technical measure. The paper introduces the landed single ball reamer about its structure composition and working principle, elaborates the application in reaming while drilling and reaming after drilling (back reaming and underreaming) with example and analyzes the application effects in different operation models.