Abstract: In order to enhance the effectiveness of Trichogramma dendrolimi as biocontrol agent, four sugar sources as a diet were set up as, T. dendrolimi fed once with 20% honey solution, continuously fed with 20% honey solution, fed once with 20% sucrose solution, continuously fed with 20% sucrose solution, and a control group of continuously fed with water. The biological parameters such as the lifespan, parasitism ability, and flight ability of T. dendrolimi was compared when were fed with different diets. The results showed that the lifespan, parasitism ability and flight ability of T. dendrolimi significantly improved when was fed with 20% honey solution or 20% sucrose solution. The T. dendrolimi wasps continuously fed with sugar solution was also better than the wasps fed with a sugar source once. The lifespan of T. dendrolimi fed with sugar solution increased significantly 2.2-22.0 days, and the number of eggs parasitized also increased by 5.9-9.9. The lifespan and parasitic ability were the best when the wasps were continuously fed with 20% honey solution, with 23.0 days and 81.1 eggs, respectively. When the T. dendrolimi wasps were fed with 20% honey solution or 20% sucrose solution, the proportion of non flying ability in the population of T. dendrolimi decreased by 6.0%-7.3%, and the proportion of flying ability at level 2 was increased by 10.9%-12.4%. These results indicated that the provision of sugar sources are beneficial for further developing the biocontrol potential of T. dendrolimi and improving its control effectiveness against maize borer and orher insect pests.