Density functional theory is one of the most successful approximate models in electronic structure calculations. In this talk, our recent works in developing numerical methods for Kohn-Sham density functional theory will be introduced. The framework of the numerical methods is built based on finite element methods. Towards the efficiency, mesh adaptivity, acceleration of self-consistent field iteration, fast solver for Hartree potential, as well as efficient LOBPCG eigensolver will be introduced in detail. In addition, the effort for the orthogonalization-free method will also be described. Numerical results will be demonstrated to show the effectiveness of our method.