Optimized design and performance investigation of one-dimension ( 1D) photonic crystal filter based on the fractal theory are performed to achieve excellent multi-channel transmissi on response and tenability.Through the analysis of fractal theory in photonic crystal structures,to control the number of channels,the parameters of the defect layer are firstly optimized to shift the corresponding channels in or out the band gap flexibly.Moreover,an optimization of the basic structure unit enables an independent tuning operation to all transmission channels.Using the transfer matrix method,the perfromance of the optimized filter is studied.Subseq uently,different numbers of transmission channels filter in four orders structur e are demonstrated,and make structure S=3as an example, the impact factors of the central wavelength of channels is analyzed,including the refractive index and width of defect layer.Th en,the filtering performance in terms of the transmissivity is quantitatively investigated,such as a 3dB bandwidth less th an 11nm and a transmission ratio greater than 0.9.The optimized design based on fractal theory provides a way for the de sign of 1D photonic crystal filter with specific channels,and it can be used in fiber communication and ele ctro-optical systems to improve signal to noise ratio of devices.