Using finite difference time domain (FDTD) method, we numerically investigate onedimensional photonic crystals (1D PCs) with (AB) m C(BA) m structure, where A and B stand for different dielectric materials, and C the graded-index (GRIN) material. The transmission properties of the multilayer structure have been studied, and the results show that a tunable narrow band-pass filter (BPF) can be obtained by changing gradient coefficients of the GRIN defect layer. For an increasing incident angle, although the transmittance becomes smaller, positions of the resonant peak remain the same, which can act as the angle-insensitive filter.