Waste plastic disposal and excessive use of fossil fuels have caused environment concerns in the world. Both plastics and petroleum derived fuels are hydrocarbons that contain the elements of carbon and hydrogen. The difference between them is that plastic molecules have longer carbon chains than those in LPG, petrol, and diesel fuels. Therefore, it is possible to convert waste plastic into fuels. The main objectives of this study were to understand and optimize the processes of plastic pyrolysis for maximizing the diesel range products, and to design a continuous pyrolysis apparatus as a semi-scale commercial plant. Pyrolysis of polyethylene (PE), polypropylene (PP), and polystyrene (PS) has been investigated both theoretically and experimentally in a lab-scale pyrolysis reactor. The key factors have been investigated and identified.High reaction temperature and heating rate can significantly promote the production of light hydrocarbons.Liquid fuel i.e. hydrocarbon fuel obtained from four different types of waste plastics low and high density polyethylene (LDPE and HDPE), polypropylene (PP) and polystyrene (PS) were carried out in a reactor stainless steel system. Each of the plastics has different chemical and physical properties so the experiments were carried out individually for each of them. Simple thermal degradation was used to melt the plastics at temperature ranging from 120 to 400 0C.Vapor condensation form the melted plastics produced the liquid hydrocarbon product. The hydrocarbon fuel which is produced is used for running the bloom car which is to be running at a maximum efficiency then other car.