Thermoelectric properties of quasi-one-dimensional (Q1D) organic crystals of n-type TTT(TCNQ)2 are investigated theoretically in order to estimate the possibility to apply this compound for thermoelectric applications. A more complete three-dimensional (3D) physical model is applied. Two the most important electron-phonon interactions are taken into account simultaneously. One interaction is similar to that of deformation potential. Three coupling constants of this mechanism are proportional to the derivatives 1 w 2 w and 3 w with respect to the intermolecular distance of transfer energies w1, w2 and w3 of an electron from the given TCNQ molecule to the nearest one along lattice vectors c, b, a. The other is of polaron type. The coupling constant of this interaction is proportional to the mean polarizability of TCNQ molecule 0  . The ratios of amplitudes of second interaction to the first one in the x direction on chains and in transversal directions y, z, respectively are described by the parameters 1, 2 and 3. The electrons’ scattering by impurities and defects is also considered. The electrical conductivity, thermopower, the electronic thermal conductivity and the thermoelectric figure of merit in the direction of conductive molecular chains are calculated numerically for different degrees of crystal purity Crystals of TTT(TCNQ)2 have the aspect of dark-violet needles of length of 3 – 6 mm. Conductive molecular chains of TCNQ are arranged along c direction, further considered as x – axis. The carriers are electrons. The transfer energy of an electron from a given TCNQ molecule to the nearest one in this direction has been taken as in TTF-TCNQ crystals, w1 = 0.125 eV. In transversal to chain directions the transfer energies w2 = d1·w1 and w3 = d2·w1 are small and the transport mechanism is of hopping-type. The parameters d1 and d2 were estimated earlier for TTT2I3 crystals. By analogy we can put d1 = 0.015 and d2 = 0.01 for TTT(TCNQ)2. In the previous paper [1] we have taken for the sound velocity along TCNQ chains the value vs1 = 2.8·103 m/s as in TTF-TCNQ crystals. However, the modeling of Peierls structural transition have shown that in TTT(TCNQ)2 the sound velocity must be larger, vs1 = 3.9·103 m/s. The average value α0 = 10 Å-3 was estimated which leads to γ1 = 1.8.  Note that the results are not very sensitive to small variation of γ1. The stoichiometric concentration of electrons in TTT(TCNQ)2 crystals was estimated to n = 1.1· 1021 cm-3 or εF = 2w1/EF = 0.35, where EF is the Fermi energy and εF is the dimensionless Fermi energy.  The thermoelectric figure of merit (ZT)xx along TCNQ chains as function of εF is presented in Fig.1.  Three different values of the dimensionless parameter describing the impurity scattering processes are considered: D0 = 0.1 as in TTT2I3 crystals growth from gaseous phase method, and D0 = 0.05, D0 = 0.02 for ultrapure crystals, not obtained yet. From Fig.1. it is observed that in stoichiometric crystals (ZT)xx ~ 0.05 even for crystals of high purity. This phenomenon is explained by the simultaneous increase of both the electrical and electronic thermal conductivity. The optimisation of thermoelectric properties may be performed by aditional dopping with donor impurities. Thus, if the concentration of electrons is increased by two times compared to the stoichiometric one, n = 2.2· 1021 cm-3 or εF = 1.05, (ZT)xx = 0.4, 0.56 and even 0.8 may be obtained, depending on crystal purity.