Abstract: In order to solve the problem of pests damage on tobacco in northern Guangdong tobacco area, with Myzus persicae, Heliothis assulta and Spodoptera litura as experiment materials, field experiment was conducted for investigating the population system of the main insect pests and their natural enemies. The results showed that Myzus persicae, Heliothis assulta and Spodoptera litura were the major pests in Nanxiong tobacco field. M. persicae and S. litura each has two population peaks each year, while several peaks occurred each year for H. assulta. The major predatory natural enemies in northern Guangdong were Coccinella septempunctata, Cyrtopeltis tenuis, Propylaea japonica, Chrysopa sinica, Harpactor fuscipes and Paederus fuscipes, while the main parasitoids were Aphidius gifuensis, Campoletis chlorideae and Microplitis prodeniae. H. fuscipes was a potential biological control agent for M. persicae, H. assulta and S. litura in tobacco fields.