Abstract: We studied modulation  of dielectric constant of dielectric column on band gap structure in the two-dimensional functional photonic crystal waveguide and the modulation of the  dielectric constant of point defect dielectric column on the electric field distribution and light propagation direction when  point defect was added into waveguide. The results show that when there is no point defect in two-dimensional functional photonic crystal waveguide，the number and position of band gap, and the number and position of detect modes can be adjusted by changing parameters  b and k  values of dielectric constant of the dielectric column.  When there is point defect in two\|dimensional functional photonic crystal waveguide， the electric field distribution and light propagation direction can be changed by changing parameters b and k values of the dielectric column with point defect.

Key words: functional photonic crystal waveguide； , function point defect； , band gap structure； , electric field distribution