The litchi fruit bOrer (LFB) Conopomorpha sinensis Bradley (Lepidoptera: Gracillariidae) is one of the most serious pests in litchi growing areas in northern Vietnam. Chemical insecticide application is a main measure to control the pest. However, efficacy of this control method is still limited due to most litchi growers are not be able to recognize the pest, to identify accurately the timing of spraying and not to use the suitable insecticides. the research results obtained in 2009 and 2010 in Luc Ngan district (Bac Giang province) showed that population dynamics of LFB aduJts were closely related to fruit phenology. They are present in litchi orchards from the flowering stage until the fruits are harvested with the main peaks stage of adult emergence occurred.when fruit - stalk started changing from green into red from the late of April to early May and from mid to the late of May in early and main crop seasons, respectively. It was found that the control LFB adults was the most effective way to reduce their infestation in the field and the best effective time for insecticide application was when LFB adults reached their peaks. Using of some insecticide and bio - insecticide compounds such as. Cypermethrin + Profenofos, Fipronil, Chlorpyrifos methyl, Cypermethrin, Abamectin + Emamectin, Abamectin, Azadirachtin + Abamectin + Emamectin, Emamectin was highly effective to control this pest (efficacy ranged from 62.33 to 82.57 percent after 7 days of treatment). It also was found that in an orchard if spraying was only applied to fruit bearing trees but not to non - bearing fruit trees then the rate of Infested fruit was 68.64 percent.