| Chilocorus kuwanae Silvestri belongs to Coleoptera, Coccinellidae, Chilocorus. The ladybird distributed in Heilongjiang, Jilin, Liaoning, Guangdong, Fujian, and others provinces in China; also recorded in Japan, North Korea, Italy, and others countries. This research most studied on its morphological, biological and function response by a systemic investigation and observation to grope for the phylogeny in Fujian, and its predation function on Hemiberlesia pitysophila Takagi. Meanwhile, preliminary study on its biological controlling in the forestry. The study provided advisable directions for using Chilocorus kuwanae Silvestri to biological control Hemiberlesia pitysophila Takagi in the forestry Fujian.1 The biological characteristics of Chilocorus kuwanae SilvestriChilocorus kuwanae Silvestri is a kind of widely distributed natural enemy ladybird in China. It can predate five branches, thirty-eight kinds of scale insects on the trees, crops, and flours, it's a kind of outstanding natural enemy insect. In the forestry of Fujian, Chilocorus kuwanae Silvestri is the main natural enemy ladybird of Hemiberlesia pitysophila Takagi, it can well control the number of Hemiberlesia pitysophila Takagi, and has a widely using prospect.Though the research in Pingtan and Fuqing towns from 2005 to 2006, Chilocorus kuwanae Silvestri happened four generations per year in Fujian province, and overwintered as adult in Cracks in the bark, crevice in stones, and litters. The time of overwinter was about in late ten days of winter to early December each year, and about early March the following year warmer temperature returned, the ladybird adults began to terminated dormancy and copulated frequently and repetitively. The survived rate of the overwintered ladybird adults was up to 86．75%, the ladybird feeding in room could alive about 86．5 days, and in natural in July also could find the overwinter ladybirds. The time of the ladybird complete its lifetime was influenced by the temperature. The higher the temperature was, the shorter the time needed; conversely, it grew slowly, and need more time to complete generation in low temperatures. The first generation larvae could be found in the late ten days of March, and through from egg to larvae, to pupa, the final adult emergence, the entire development process lasted about 57 days. The second generation and the third generation ladybirds as high temperatures, rapid growth, the average development period ranges were only 32 days and 31 days. The fourth generation ladybirds eggs emerged in middle ten days of September, the latest adult emerged in early December, around the end of December into the winter. The lives of every generation adult ladybirds were difference, and the overwinter generation had the longest lifetime, average 217．9 days; the second generation had the shortest lifetime, only 109．2 days. The reason might be related to the change of the climate. The adults emerged, developed some times to become sexual maturity, frequently copulated and lay eggs. Along the lifetime, the adults could be repeated copulated, and the copulated time varying duration. Some times after copulated, the adults became to lay eggs, and the time of laying eggs were different along the spawning season. The first generation emerged the same time to the time that Hemiberlesia pitysophila Takagi occurred strongly, so the ladybirds could get more food, lay more eggs, average 152．7 eggs per ladybird.Chilocorus kuwanae Silvestri had strong hunger tolerance, which changed with the time the ladybird grown after emerged. Naturely, Chilocorus kuwanae Silvestri had some properties, such as it could die away, and its activities site, laying sites were hidden, which could help them established a stable species in the forestry, and maintain their population.2 The functional response of Chilocorus kuwanae Silvestri predation on Hemiberlesia pitysophila TakagiUnder laboratory conditions, the equation of Holling-II could be well used to describe the functional response of Chilocorus kuwanae Silvestri predation on Hemiberlesia pitysophila Takagi. The predate capability of Chilocorus kuwanae Silvestri increased as its age older, and the predation number was gradually converge to a maximum. And the predation number equation of the adults and fourage old larvals were(?) and(?).The maximumpredation number every age old ladybirds were: one-age-old larval 21．73; two-age-old larval 23．55; three-age-old larval 33．10; four-age-old 48．47; and the adults had the biggest predation number, was 56．69 per day.The predation capability of Chilocorus kuwanae Silvestri was not mater influenced by the prey density and its age, but also changed with the temperature and its density. In the same treatment, the higher the temperature was, the greater the predation capability was. The reason was that, as the temperature increased the ladybird and the prey activity became stronger, the instantaneous rate of discovery of the ladybirds was stronger, and the time spent handling was shorter, the ladybird could easily caught the prey. From the result of experiment, the predation ?capability of Chilocorus kuwanae Silvestri was the best at 29℃. Also, at the same outer environment, as the increase of the density of predators, the interference between each predators was stronger, and the predating capability of the predators became weaker. At the room temperature, the equation of predation rate was:E=0．5434QP-1．3840 ,r2=0．9951。By the same way, the sheath could influence the predacious function of Chilocorus kuwanae Silvestri. From the experiments, Chilocorus kuwanae Silvestri could predate Hemiberlesia pitysophila Takagi inside or outside sheathes. But it could efficiently predate the Hemiberlesia pitysophila Takagi outside sheathes, the predate rate was up to 77．2%. To Hemiberlesia pitysophila Takagi outside sheathes, the ladybird could tore the sheathes, and predated the scale insects inside.3 Preliminary study on the biology controlling in the forestryChilocorus kuwanae Silvestri had the strongly predate capability on Hemiberlesia pitysophila Takagi, the ladybirds could well control the occurrence of scale insects. Inoculating the scale insects in the coop on the tree in forest and released the ladybirds in the coop, thirty days later the scale insects number decreased 74．6%, from 11．43 per pine needle to 2．87 per pine needle. Besides,there were not any Hemiberlesia pitysophila Takagi outside the sheathes.And released the ladybirds naturally, the average density of Hemiberlesia pitysophila Takagi dropped from 6．0625 to 1．8575 per pine needle, the parasitical ratio of the scale insects also down from 55．5% to 29．55．The biology controlling was well. Comparatively, the pines without the ladybirds were badly damaged by Hemiberlesia pitysophila Takagi.
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