The electronic structure of pure CoSb3 (undoped) and the electronic transport properties as a function of chemical potential (mu) of CoSb3 under different pressures were studied systematically and in detailin our research. Direct band gap change to indirect band gap with increasing pressure was found for the undoped CoSb3. The electrical conductivity of undoped CoSb3 significantly decreases with increasing pressure from 0 to 10 GPa, the Seebeck coefficient of undoped CoSb3 significantly enhanced with increasing pressure. The n-type of doping in CoSb3 would be more favorable for enhancing the thermoelectric properties than that of p-type doping under pressure. (c) 2012 Elsevier B.V. All rights reserved.