Objective To research Dengue virus type 2 (DENV-2) to human umbilical vein endothelial cells (HUVEC) permeability. Methods The titration of DENV-2 was detected and HUVEC infection DENV-2 layer of cells. At different time points after infection (30 min, 1 h, 3 h, 6 h, 12 h, 30 h,36 h, 24 h, 42 h, 48 h,72 h), the permeability in HUVEC were detected after Dengue virus infection. The virus load in HUVEC was detected by quantitative real-time PCR. And ultrastructure in HUVEC was observed by electron microscope. Results The permeability in HUVEC was changed after Dengue virus infection by time lasting. The most permeability in HUVEC was changed after Dengue virus infection at 30 min and 42 h. And at the same time the virus load were most value in all of time. The results of the cell membrane were changed by electron microscope. The deciduous cell microvillus and dissd endochylema were founded. And some of nuclear membrane blank was wided by Dengue virus. Even the leakage was founded in cell nucleus. The other change included that disappearance mitochondrial and vacuolization crista, elder pith change mitochondria. In addition, the complete of cell membrane were dissolved. Conclusion The permeability of HUVEC was changed by DENV-2. To explore the pathogenesis of Dengue virus provide certain theoretical basis.