The aim of this study was to evaluate the anti-cancer effect of a novel organoselenium compound BBSKE (1,2-[bis(1,2-Benzisoselenazolone-3(2H)-ketone)]ethane, BBSKE, PCT: CN02/00412) on cell growth and apoptosis, focusing on the protein activity of Thioredoxin Reductase (TrxR) and Caspase-3, in oral squamous cell carcinoma (OSCC) in vitro and in vivo. Oral squamous cancer cell line Tca8113 was treated with various concentrations of BBSKE. Growth and apoptosis as well as the protein activities were analyzed. Morphologic changes of Tca8113 cells after 24h treatment of BBSKE were determined by fluorescence microscopy. The increase of Caspase-3 activity and decrease of Thioredoxin reductase (TrxR) activity were also measured. BBSKE induced a significant cell growth inhibition and elicited typical apoptotic morphologic changes (chromatic condensation, nucleus fragmentation). This phenomenon was accompanied by a change in protein activity of Thioredoxin reductase (TrxR) and Caspase-3. The anti-cancer effect of BBSKE was then studied in well-established Tca8113 xenografts in nude mice. In those tumors, anti-cancer effects were observed and significantly higher than the controls. Together, these results indicate that BBSKE can inhibit tongue cancer cell proliferation in vitro and in vivo, and induce apoptosis in Tca8113 cell lines partially via inhibiting the activity of TrxR and promoting the activity of Caspase-3.