Ericerus pela is very harmful to the local Glossy Privet,the first generation larva of Ericerus pela is an important chemical control period.In order to accurately forecast the appropriate control period，the relation between the first generation of Ericerus pela and local temperature were studied.The results showed that the period with local average temperature 20~23℃ or thermal summations of 933.9~1 588.9℃ after Glossy Privet germinating was a critical period of chemical control to the first generation larva of Ericerus pela.