In　the　present　study,　cultured　human　SHG-44　glioma　cells　were　subjected　to　a　hypoxic　environment　simulated　using　the　CoCl2　method.　Flow　cytometry　showed　increased　reactive　oxygen　species　production　in　these　cells.　Real-time　reverse　transcription-PCR　showed　significantly　increased　hypoxia-inducible　factor-1　alpha　mRNA　expression　in　cells　exposed　to　the　hypoxic　condition.　The　antioxidant　N-acetylcysteine　significantly　inhibited　reactive　oxygen　species　production　and　reduced　hypoxia-inducible　factor-1　alpha　mRNA　expression　in　normoxic　and　hypoxic　groups,　especially　in　the　latter　group.　These　findings　indicate　that　hypoxia　induces　reactive　oxygen　species　production　and　hypoxia-inducible　factor-1　alpha　mRNA　expression　in　human　SHG-44　glioma　cells,　and　that　the　antioxidant　N-acetylcysteine　can　inhibit　these　changes.