Disclosed is a back rest structure for vehicle seats and a method for manufacturing the same. The back rest structure has a back panel element and a seat back frame element fixed to each other, where at least one of the back panel element or the seat back frame element is provided of a thermoplastic composite material comprising a thermoplastic compound material and a reinforcement material, wherein with respect to the thermoplastic material the reinforcement material represents 50 wt-% or more than 50 wt-%.