The invention relates to a single-circuit linear tower middle-phase combination bird-preventing device and a using method thereof, belonging to the overhead power transmission line bird damage prevention technology field. The technical scheme of the single-circuit linear tower middle-phase combination bird-preventing device comprises that: a small-sized strong magnetic reflection windmill bird-repelling device is arranged on a main material of an upper surface of a middle-phase cross beam and is absorbed to angle steel through a strong magnet 1; a bird-preventing isolation fence of the single-circuit linear tower is arranged in a middle gap of the middle-phase cross beam and is supported on the angle steel on the upper surface of the middle-phase cross beam through falling-preventing plates; the bird-preventing fence is fixed in the middle gap of the middle-phase cross beam; a plurality of small-sized strong magnetic stainless steel bird needles are arranged around an insulator hanging point and are absorbed to the angle steel of the cross beam through a strong magnet 2. The single-circuit linear tower middle-phase combination bird-preventing device is small in volume, light in weight and long in service life and cannot be corroded. The single-circuit linear tower middle-phase combination bird-preventing device uses strong magnetic materials to install, and is easy to dismount, not limited in installation position and direction and movable. Furthermore, the single-circuit linear tower middle-phase combination bird-preventing device and the using method thereof not only prevent birds from nesting on the normal bird needles, but also provide convenience to maintenance personnel for upkeep.