In this work, high vacuum (10-6 Torr) annealed (at 500°C) samples of the thermoelectric materials Bi2Te3 and Sb2Te3 were analyzed in terms of local structures and electron density distribution. After annealing, the samples were analyzed for their structural properties using powder X- ray diffraction data. The electron density distribution has been analyzed using the MEM (maximum entropy method) and the precise bonding in Bi2Te3 and Sb2Te3 has been determined. Since Bi2Te3 and Sb2Te3 and their combinations are the latest high figure of merit thermoelectric materials, with immediate application in many fields, particularly the electrical power harvesting devices, a study on the local structure of these materials becomes important which has been carried out in this work. Also the particle size variation due to annealing effect is studied and reported and the bond distance between neighboring atoms in bismuth telluride and antimony telluride has been analyzed.