A metamaterial for deflecting an electromagnetic wave is disclosed, which comprises a functional layer. The functional layer comprises a plurality of sheet layers parallel to each other, and each of the sheet layers comprises a sheet-like substrate and a plurality of man-made microstructures arranged in an array on the sheet-like substrate. The sheet-like substrate comprises a plurality of unit blocks, and each of the man-made microstructures and a corresponding one of the unit blocks occupied thereby form a unit cell. Refractive indices of the unit cells arranged in a first direction in each of the sheet layers decrease gradually. Each of the unit cells has an anisotropic electromagnetic parameter. Through use of the metamaterial of the present disclosure, deflection of the electromagnetic wave can be achieved.