An optical waveguide apparatus including a first dispersion unit and a separation unit. The first dispersion unit is connected to the separation unit, the first dispersion unit is configured to disperse a frequency component of at least one first optical signal, and the separation unit is configured to separate, into at least one second optical signal based on configuration information, the frequency component that is of the at least one first optical signal and that is dispersed by the first dispersion unit. The separation unit is implemented by a variable optical waveguide, and the variable optical waveguide is an optical waveguide that implements at least one of the following functions based on the configuration information: forming an optical waveguide, eliminating an optical waveguide, and changing a shape of an optical waveguide.