In this study, reactive polyolefins were synthesized from fatty acids and subsequently functionalized. Pd-catalyzed decarbonylative elimination of fatty acids afforded corresponding alpha-olefins in good yields. Site-selective and stereoregular polymerizations of M0 (from stearic acid), M1 (from oleic acid), and M2 (from linoleic acid) monomers were performed using Et(Ind)(2)ZrCl2/MAO (methylaluminoxane) catalysts. The reactivity of these monomers for polymerization decreased with the increase in the number of internal olefin moieties. The resultant polyolefin (P2) from M2 exhibited auto-oxidation behavior at the internal olefin moieties. The internal olefin moieties of P2 had higher auto-oxidation reactivity and lap shear strength to glass substrate than those of P1 obtained from M1. Additionally, various postfunctionalization reactions of P1, such as bromination, epoxidation, and cross-metathesis, were performed. A quantitative conversion was achieved for the bromination and epoxidation reactions of P1 in a single step. The applications of functionalized P1 significantly broaden the range of applications.