Utilizing the finite difference time domain (FDTD) method, energy eigenvalues of spherical, cylindrical, pyramidal and cone-like quantum dots are calculated. To do this, by the imaginary time transformation, we transform the schrödinger equation into a diffusion equation. Then, the FDTD algorithm is hired to solve this equation. We calculate four lowest energy eigenvalues of these QDs and then compared the simulation results with analytical ones. Our results clearly show that simulation results are in very good agreement with analytical results. Therefore, we can use the FDTD method to find accurate results for the Schrödinger equation.