Aim To investigative nicotinamide adenine dinucleotide phosphate oxidase(NOX4) expression,intracellular reactive oxygen species(ROS) level and cell apoptosis in human umbilical vein endothelial cells(HUVEC) when stimulated with high concentration of glucose.Methods Morphology of HUVEC was observed with inverted microscope,expression of factor Ⅷ related antigen in HUVEC was detected by immunofluorescence.NOX expression in HUVEC was convicted by reverse transcription polymerase chain reaction(RT-PCR) with positive control.Intracellular ROS generation was measured by DCFH-DA,cell apoptosis were measured by PI and Hoechet 33342 staining respectively.Results With high glucose in media,expression of NOX4,intracellular ROS generation and cell apoptosis were all increased.Conclusions High glucose could upregulate NOX4 expression,intracellular ROS production and then lead to cell apotosis.