Thermal stability of conductive charge transfer complexes of poly(4-vinylpyridine)-poly(dimethylsiloxane) (P4VP-PDMS) block copolymers with tetracyanoquinodimethane (TCNQ) was investigated by using thermal gravimetric analysis (TGA). The results show that both TCNQ simple and complex salts of polymers are thermally stable up to 800 degrees C and depending on the amount of added neutral TCNQ, the residual product increased up to 75%.