Abstract: By studyng the biology, release techniques and control effect to Monochamus alternatus of Scleroderma guani Xiao et Wu,the results show that:(1)Scleroderma guani can complete its propagation on the larva of Monochamus alternatus in Jiangsu;(2)The optimum release technique is the model of release Scleroderma on single dying tree or weak tree in one point per hectare release 80～100 trees.After 1 month the parasitic results are checked.The rate of parasite of Scleroderma guani to the larva of pine sawyer beetle(PSB)can reach 48.68%.It is higher than the rate of parasite of 37.50% to ues the model of point release method;(3)The optimum release wasp time is in the second ten days of July.Its parasitic rate of Scleroderma guani to the larva of PSB can reach 37.50%～66.82%,which is higher than that in August;(4)The optimum density of release wasp is 5 000 wasps/hm 2 .The rate of parasite is 48.68%.It is very near release 10 000 wasps/hm 2,which the rate of parasite is 52.86%; (5)After releasing wasp in the area of 540 hm 2 the rate of parasite can get 33.33%～66.82%.The Rate of dead trees which was caused by pine wood nematode( Bursaphelenchus xylophilus ) (PWN)reduced 98.0% after release wasp in the test field.The test results show that Scleroderma guani can effectively control PSB & PWN in test field.