Metamaterials are a class of materials that achieve novel properties from artificial structures, and expected to be the source of a series of disruptive technologies. These artificial materials are completely different from conventional materials in their basic structures, properties and synthesis methods. The interface between them is clearly distinct——conventional materials come from nature, easy to obtain and difficult to design; metamaterials are the opposite, easy to design, but usually difficult to obtain. We proposed a strategy for development of new functional materials by merging of metamaterials and conventional materials. Based on this approach, we have developed dielectric electromagnetic metamaterials, natural abnormal electromagnetic media, and a series of conventional materials based on the idea of metamaterial design. A new concept, generalized metamaterials, is formed on this basis, to expand the scope and significance of metamaterials, and provide a new way for improving properties of materials.