The modeling of dendritic crystal growth of highly anisotropic materials is important in understanding the physics of nature phenomena, such as snow growth, and industrial processes, such as polycrystalline silicon growth. Phase-field modeling has emerged as a powerful tool in such a simulation, but the description of the anisotropic function for three-dimensional (3D) interfacial energy without miss-orientation remains quite difficult. In this paper, a simple method is proposed in our 3D adaptive phase field model. The simulated equilibrium shapes with different anisotropic strengths are first compared with the exact solutions, and they are in good agreement. The dendritic growth of a pure material with different anisotropic strengths for various supercoolings is further simulated, and the morphologies are discussed.