[Objective] The purpose was to supply reference basis for studying invasion region of Metarhizium anisoplia in Brontispa longissima, invasion process and its control measures. [Method] The surface of B. longissima naturally infected by M. anisoplia which were collected from field were scanned and observed by scanning electron microscope. [Result] The regions naturally infected by M. anisoplia on surface of B. longissima included not only arthrodial membrane between abdomen and prothorax, but also both sides of abdomen and the rear part of end node of abdomen, where a large amount of structural material closely related to infection had been formed and observed, such as infection peg, mycelia and spore. [Conclusion] Damage degree of insect surface were different when M. anisopliae infected B. longissima under different environmental conditions, such as nutrient material, PH value, temperature and humidity, etc.
