Change the chemical composition of compounds based on PbTe, including doping by Ag and Sb allows to obtain materials with thermoelectric figure of merit at (2,2 ... 2,4) [1,2]. However, obtaining the same or similar values of Seebeck coefficient, electrical and thermal conductivity for samples of n- and p-type is not always possible. The influence of the chemical composition and manufacturing conditions of thermoelement's legs on their parameters was analyzed in this work.   Compounds were synthesized by direct fusion method with forced mixing of components. Samples for research were cylindrical shape and were made by cold pressing at pressures (1.5 ... 2) GPa with subsequent low-temperature annealing at temperatures (230 ... 300)°C in air. The research results of influence of changes in the chemical composition on the temperature dependence of the Seebeck coefficient are presented. It was established, that the numerical values of the Seebeck coefficient can be optimized for close range, as shown in Fig.  However, the coefficients of electrical and thermal conductivity vary in the range (4 ... 6)%. This may be due to changes in the concentration of charge carriers and their mobility.