Soluble block and graft polystyrene-polythiophene copolymers have been synthesized. These block copolymers are prepared by polymerization of Thiophene (T) or 2-bromo T on thiophene groups attached at the end of polystyrene chains . In these syntheses it is observed that the length of PT sequences increases with the length of Polystyrene block..Uv/vis , and I.R.spectroscopies show that the PT blocks are made of long conjugated sequences.These copolymers are aggregated in solutions (GPC and Light scattering data). The reaction of FeCl3 (in acetonitrile) on copolymer chloroform solution was followed by UV/Vis/NIR spectroscopy. A doping equilibrium is observed. Copolymers films can be converted in pure PT films by heating at 380-degrees-C under vacuum or argon which depolymerizes PS sequences.The morphology of these PT films can be controlled from sphere monolayers to fibrillar films. They are doped by FeCl3 with conductivity up to 60 S/cm.