The discrete optimal orientation design of the composite laminate can be treated as a material selection problem dealt with by using the concept of continuous topology optimization method with multiphase materials.In this work, the so-called bi-value coding parameterization (BCP) scheme developed recently by the authors is applied in the optimization design of laminated composites related to the compliance minimization and maximization of natural frequency.The basic idea of the BCP scheme is to "code" each material phase using integer values of+l and-1 so that each available material phase has one unique "code" consisting of+l and/or-1 assigned to design variables.Besides, a new form of the volume constraint is introduced in accordance with the BCP to control the material usage and material removal in the corresponding problem formulation.Meanwhile, a general set-up strategy is proposed by assigning "uniform" weight values in BCP to ensure the feasibility of the initial starting point.