Abstract: From 2004 to 2007,under the walk-over survey and sample plot investigation,10 orders 93 families and 679 species of tender shoot and leaf forest insects belonging to 93 families of 10 orders(Acarina included) were found in Qilian Mountains Nature Reserve.The occurring characteristics and area of the main tender shoot and leaf forest pests were identified and the occurrence reasons were analysed.Losing quantity of Picea crassifolia under tender shoot and leaf forest pests damaged were also investigated.The correlation model between pest density,leaf loss rate,fresh weight of damaged branch and growth,quantity loss rate of diameter breast height were set up,and the correlation model between pests rate of P.crassifolia and fresh weight of tender shoot and leaf were also concluded.