The tuning characteristics and quality factor of one-dimension photonic crystal micro-cavity with symmetrical structure and unsymmetrical structure with transfer matrix method were researched.Results show that with the increase of optical thickness of defect layer，the center wavelength of defect mode will increase and tuning characteristics of micro-cavity relate to the refractive index of medium which surround the defect layer.Compared with symmetrical structure，unsymmetrical structure can achieve linear tuning with wide wavelength range but smaller variation of the optical thickness of defect layer.Quality factor will increase first and then reduce with increase the thickness of the defect layer and it has maximum when the center wavelength of defect mode is λ0.The array of medium with high or low refractive index affects the quality factor of micro-cavity.