These studies were conducted to carry out mechanism and site of gall formation by Schlectendalia chinensis in Rhus javanica. The formation period of gall hy occurrence of fundatrix was middle of June, and fundatrix was settled and parasited on back side of immature leaves and tissues of Rhus javanica was ride to fore face, then formed Schlectendalia chinensis gall. Scl~lectendalia chinensis was suddenly developed in middle of Auguest. As the density of Schlectertdalia chinensb increases, the Schlectendalia chinensir gall was more plumped. The part of phyllotaxy of Schlectendalia chinensis gall in leaf and pinnate of was increased in closer pan of terminal leaflet and leaflet was more occupied then wing.