Derived from palm Fatty Acid Methyl Ester (FAME), high quality biodiesel called H-FAME has been introduced in order to increase its percentage blended with diesel. Due to monoenen-rich FAME by partial hydrogenation process, H-FAME is superior oxidation and thermal stability. In the current study, the effects of 20 percent of high quality biodiesel blended with diesel (B20) on the compatibility of polymeric engine parts have been investigated by means of the immersion test. Pure diesel has also test as the reference. Following SAE J1748 in conjunction with ASTM D471, selected commercail engine parts such as fuel hose and tank were immersed in the test fuels. In addition, Viton (fluoro elastomers), neoprene and nitrile butadiene rubber (NBR) were also soaked for comparison. Apparent percent weight increase was used to indicate the change of the engine parts after exposed to the test fuels. Mechanical properties, tensile test, was measured to manifest the compatibility of elastomers. Depended on their based-constitution, each engine parts showed the different change, hence increase or decrease. Neat diesel seemed to be absorbed in the elastomer while high quality biodiesel had the capability of dissolving. Plastic material and viton could tolerate well with the H-FAME.