The optical waveguide has the characters such as: simple structure, small physic volume, bearing the corrosion, good insulation, easy to integrate etc., and is sensitive to the changes in parameters such as: refractive index, absorption, the processes of light emitting such as chemiluminescence or fluorescence. These changes modulate the light transmitting in the waveguide. These characteristics can be used to make many kinds of sensors. The optical waveguide biosensors are the combination of the techniques of optical waveguide chemistry and bioengineering and will play a very important role in the biochemistry field. This article summaries several kinds of optical waveguide biosensors having been developed and compares their characteristics.