Making polymer alloys, copolymerization, functionalization, preparing polymeric composites using inorganic components or adding additives such as plasticizers and stabilizers to polymers are new strategies to modify polymers suitable in new applications. Among these methods, functionalization of polyolefins counts as a useful strategy for synthesis of new materials with improved properties. Functional groups change the important properties of polyolefins such as adhesion, penetration, compatibility, resistance to solvents, rheological and surface properties like colorability and printability, therefore, the functionalization can extend their application to other fields including adhesives, colors and insulators.To obtain a polymer with some particular properties, besides the type of functional groups, it is necessary to control their contents. Therefore, development of methods for controlled synthesis of functionalized polyolefins by conventional industrial monomers has achieved great interest in academic and industrial research. In this paper, several different methods for synthesis of functional polyolefins, their properties and applications are discussed in brief.