In recent years the importance of automotive industry that is growing and changing continuously is increasing. Automotive industry has 5% share of world economy. With the rise in progress in automotive sector, the studies about the use of environmentally friendly components in weather-strip sealing systems also increase and becomes more important. Petroleum based paraffinic and naphthenic oils are used as plasticizer in EPDM compound mixtures. In this study, the auto-oxidation of herbal based renewable flax seed oil that is based on free radical chain reaction was occurred at room temperature for 15, 45, 90 and 120 days separately. The possibility of using flax seed oil that contains hydroperoxides after auto-oxidation reaction instead of petroleum based oils was investigated. The rheological properties of obtained rubber compound was defined wit MDR ( Moving die rheometer), Mooney viscosity, Mooney scorch and rubber process analyzer (RPA). The mechanical properties such as hardness, elongation, tensile strength before and after aging at 90C for 4 days, density and permanent set properties were measured. Also, the thermal properties of samples were characterized with TGA. Keywords: EPDM, Vegetable Oil, Rubber, Flaxseed Oil, Auto Oxidation References [1] Selin Hande B. 2015,Formatıon Of Epoxy Fatty Acids During Autoxidation Of Linseed, Sunflower and Olive Oil Thesis (M.Sc.) -- Istanbul Technical University, Institute of Science and Technology, 2011 , Istanbul. [2] Hazer B, Keleş E, “Auto-oxidized Polyunsaturated Oils/Oily Acids: Post‐it Applications and Reactions with Fe(III) and Adhesion Properties”  Macromolecular Symposia 269(1):154 - 160 · August 2008 with 28 Reads [3] Wee, Sim Choo John Birch Jean, Pierre Dufour” Physicochemical and quality characteristics of cold-pressed flaxseed oils” Journal of Food Composition and Analysis Volume 20, Issues 3–4, May 2007, Pages 202-211 [4] Alli A and Hazer B. “Poly(N-isopropylacrylamide) thermo responsive cross-linked conjugates containing polymeric soybean oil and/or polypropylene glycol” European Polymer Journal 44 (6), 1701-1713, 2008.