Motivated by key advances in additive manufacturing techniques, the tailoring of materials to achieve unique properties such as stretchability or energy dissipation has been the focus of research over the past decade. However, it is challenging to derive optimization algorithm to design these metamaterials due to their highly non-linear nature. Also, existing density-based optimization methods often yield designs having non-smooth surfaces and a large number of small intricate features, which are difficult to manufacture even by AM. To overcome these difficulties, a new topology optimization method based on the Bezier curve is proposed. To demonstrate the ability of designing lattice metamaterials using the proposed method, two different metamaterial designs are presented, one design is to tailor lattice material to present super stretchability under large deformation with fully recoverable properties. The other design is to optimize buckling-induced energy dissipation lattice material to achieve desired energy dissipation capacity.