Autophagy is a catabolic process for the maintenance of cellular homeostasis and is also important in times of stress, including viral infection. Recently we found knockdown of three authophagy genes, ATG5, ATG8 and ATG18, significantly reduced the transcriptional levels and tiers of dengue 2 virus(DENV2) in Ades aegypti. We also found that DENV2 transcription level was significantly reduced after autophagy was blocked by 3 methyladenine or L-asparagine and was significantly enhanced after authophagy was induced by rapamycin. Western blotting analysis also demonstrated that level of the LC3-II, the widely used biomarker of authophagy, was significantly increased in DENV2-infected mosquitoes at 24h post inoculatin(p.i.) and reached the maximum at 48h p.i. Then is gradually declined but remained detectable at 96h p.i. Subsequently, our results suggested that in vector mosquitoes, DENV2 can activate autophagy machinery that is favorable for viral replication.