Abstract: The experimental research and analysis of 1.31 μm single-mode channel waveguides and components fabricated by annealed proton exchanged (APE) technique in X cut,Y proagation LiNbO3 are presented.The near field mode intensity profile of optical waveguides under various proton exchange time (te) and annealed time (ta) are measured.The optical waveguide mode size matching well with singlemode fibre is obtained by measuring and comparing with that of a single mode fiber.The lowest insertion loss of fibre waveguide fibre is 3.2 dB.The low frequency modulation characteristics of M Z interferometric modulator modulator formed in APE waveguides are tested.