This invention disclses a production technique of factory-producting microsporozoon, which uses cultivated silkworm as the host. The microsporozoon has the specificity of being very wide to parasitic insects. In this technique we choose cultivated silkworm as substitute because its feeding technique is maturate, and it is easy to feed and propagate, and it can be feed by many times all through a year. Artificially creat infected sickness condition to achieve mass reproduction of the aimed microsporozoon. The hos cultivated silkworm has such advantages as big body, mass yield, low feeding cost, scalizable feeding, industrializable producting, consequen- tly the resource difficulty of microsporozoon is resolved.