One of the problems in industry, diesel engines, thermal power plants and ships is how to create petroleum wax deposits. Oil composition, temperature and pressure are effective factors causing wax precipitation. One way to prevent wax precipitation is use of chemical inhibitors to reduce pour point. Investigation into the effects of additives on specific oil samples might help solving wax precipitation problems at various oil processing stages. Despite previous studies that have been done at this aim, finding materials that can decrease the pour point and that can be economically acceptable and can be economically and environmentally well optimized and acceptable is still an unsolved problem. So it’s important to use effective materials that can act on prevention of wax precipitation, or on decrease of the amount of precipitation and thus decrease the pour point temperature. In this study, effects of industrial polymer additives and economically acceptable surfactants have been investigated on decrement of pour point temperatures of three oil products samples, namely light diesel, heavy diesel and fuel oil, all of which were produced by Esfahan Oil Refining Co. Meanwhile, optimized type and concentration of additive were studied in choosing the additives. Findings indicated that the highest temperature decrease was observed for light diesel which was 18 ?in 28% ethylene-vinyl acetate copolymer with 5000 ppm of concentration. Furthermore, regarding heavy diesel, the highest decrease in the amount of temperature in pour point of heavy diesel was 24 ? in copolymer with 2000 ppm of concentration with 28% vinyl acetate. Also, unlike light diesel, active surfactants such as Oleic Acid, Stearic Acid and Coconut Fatty Acid Diethanol Amid are effective in decrease of pour point temperature, with Oleic Acid being the most influential one. Concerning Acid Fuel, ethylene-vinyl acetate copolymer with 19% of concentration was the best efficient in prevention of formation of wax crystals, in a way that the amount of pour point temperature occurred was the most, i.e.15 ?, in 1000 ppm of concentration. Moreover, it was shown that the copolymer ethylene vinyl acetate 28% at a concentration of 500 ppm reduced the pour point temperature by 12 ?C for diesel, also the copolymer ethylene vinyl acetate 19% at a concentration of 300 ppm reduced the pour point temperature by 9 ?C for fuel oil. All in all, making use of copolymer ethylene vinyl acetate was recommended as an industrially economical substance. Key Words: pour point, ethylene-vinyl acetate copolymer, diesel, fuel oil, wax.