Coupling characteristics between photonic crystal waveguide and micro resonator have been studied by using coupled-mode theory,and then two types of symmetrical waveguides based on 5×5 micro resonator are designed in the two dimensional square-lattice photonic crystal.The transmission characteristics of the waveguides are studied by the time domain finite difference method.The results show that different resonant coupling modes between waveguide and micro resonator are introduced by changing radius of the defect rod at the center of the resonator.Finally,nine pass bands are achieved.Both of the waveguides have the characteristics of narrow pass bands which shift towards lower frequency as radius of the defect rod increases.For the same resonator,the side coupling waveguide has lower output signal strength decay at central frequency than the directional coupling waveguide,and the side coupling waveguide has achieved more strength resonant coupling between waveguide and micro resonator.As signal processing interfaces,the two micro waveguides can be used to design narrow pass band filters,network interconnection devices,and they have applicable value in the fields of optical communications,integrated optical circuits,spectral sensors,etc.