The temperature dependence of Seebeck coefficient (S) for p-6H-SiC has been obtained. It increases from 2 up to 5.2 mV/K when temperature decreases from 400 down to 240 K. It is shown that phonon drag effect makes critical contribution to the S value. Improved theoretical model involving 4-phonon scattering process has been proposed for the simulation of Seebeck coefficient phonon pail.