Lead telluride and its solid solutions are perspective materials for a photo- and thermoelectric converters [1]. PbTe crystallises with a considerable deviation from stoichiometry and concentration of vacancies in lead and tellurium sub-lattices in crystals of this compound reaches 1019cm-3. Besides, samples contain various defects formed at synthesis and growth of crystals. In present paper influence of structural defects on lattice heat conductivity of PbTe and Pb1-XMnXTe (х=0,04) single crystals grown by Bridgman method in the range of 77-300 К have been investigated. A lattice part of the heat conductivity of samples was calculated from expression L = o - э = o – LσT, where o and e are total and electronic components of the heat conductivity, L - Lorentz number, σ – electrical conductivity of the sample. For a parabolic zone in case of arbitrary degeneration and elastic scattering of the charge carriers e =А (к/е) 2σТ, where e – electronic charge, k – Boltzmann constant, and value of A was determined from experimental values of thermo-e.m.f. factor on curve А=f ( ) [2, 3]. It is shown that in investigated non-annealed single crystalline samples heat is transferred, basically, by lattice vibrations and the electronic component e in samples does not exceed 1 % for PbTe, and for Pb1-XMnXTe with х=0,04 it makes 9 % from the total heat conductivity. With temperature growth, thermal resistance of the crystal lattice (WL) linearly grows in the sample that testifies that WL created basically, due to phonon-phonon scattering. From the temperature dependence of WL thermal resistance created by structural defects was determined, which for non-annealed PbTe and Pb1-XMnXTe samples equals 1.7 and 13.0 W-1 cm K accordingly. Annealing of the samples at 670 K during 120 hours in argon atmosphere leads to reduction of additional thermal resistance and growth of charge carrier mobility in them. Therefore it is supposed, that additional lattice resistance in studied non-annealed samples is caused by the structural defects formed at synthesis and growth of single crystals. Concentration of this sort of structural defects were calculated which equals 1017 cm-3 that is in a good agreement with Hall concentration of the current carriers in samples at 80 К. After annealing electronic component of the heat conductivity of Pb1-XMnXTe samples increases to 15 %. Also the factor entering into expression for effective cross-section of phonon scattering (s = d 2) on Mn atoms in Pb1-XMnXTe crystals was calculated which has appeared equal 0.47. This value that is less than unity, accord well with the fact that manganese atoms replace lead atoms in PbTe lattice.