Abstract: In this paper the characteristics of Ordinary cylindrical worm drive are summarity analysed, The authors have made scientific experiments and industrial practice. According to the basic principle of lubrication and put for ward new methods f raising load bearing Capcity, such as machining worm wheels by,gearing tools,Shaving and modefying worm -wheels and reasonably selecting standancal lubricant oil etc, So as to prove the forming of good hydraulical lubricant film between two conjugate surfaces.These methods prosses a certain basis of theory and practice and are of simple manufacturing technology excellent effect. They are widely used in industry and have a promising prospect.