Abstract: In the field of integrated optics, optical wavelength splitters is a key element in light signal redistribution. A optical wavelength splitter was presented for 1.31m and 1.55m wavelengths with TE mode. The device was based on the operating principle of a directional coupler in two parallel LiNbO3 photonic wire, and can be designed and simulated by finite element method. The calculated steady-state field distributions indicate that the wavelengths of 1.31m and 1.55m light waves are spatially separated. In this device, transmittances at the 1.31 and 1.55m wavelength are 91% and 86% respectively. The size of this device is only 26.2m10.1m.