A precise integration time domain method was proposed to study the transmission properties of twodimensional photonic crystals, and its accuracy, efficiency and stability were also analyzed. The Yee′s difference technique was employed to discrete the first order Maxwell equations in the spatial domain. Considering the boundary conditions and the expression of the excitation, the equations were transformed into a set of ordinary differential equations. Then the time step was precisely divided, and the ordinary differential equations were solved by using the high precision integration. The reflection and transmission field distributions of the photonic crystal were obtained by combining the general solution with the particular solution resulting from the excitation. Finally, the transmission properties of the photonic crystal were obtained by Fourier transformation. Practical calculations of the twodimensional photonic crystals were carried out. The results show that the precise integration time domain method is more accurate, stable and efficient than the finite difference time domain method.