The thermoelectric power of bulk specimens of the system Bi1-xTex (0.3£ x £ 0.6 at.) was studied. The effects of Te content, temperature and time of annealing were considered. For most of the compositions considered, the activation of holes seemed predominant. The electron activations, as well as mixed activations, seemed dependent on Te content and the conditions of annealing. Compensation semiconductor behaviour could also be observed. However, both the value and polarity of the Seebeck coefficient seemed dependent on Te content, conditions of annealing and the temperature of measurement.