The transmission matrix method theory was applied to study the localized electric field inside the one-dimensional photonic crystal quantum well of double barrier (AB)k(CD)m(DCD)n(DC)m(BA)k. The result shows that a strong electric field, which will become stronger as approaching the well center, is distributed inside the photonic crystal quantum well of double barrier. When barrier layers of the well thicken, especially the inner and outer barrier layers thicken simultaneously, the localized electric field rapidly strengthens, and the react is most obviously in the center of the well. When the well layers widen, the closer to the well center, the stronger the electric field is. But when the well layers widen by even multiple, the localized electric field in the well center remain steadily in maximum value. While when the well layers widen by odd multiple, the intensity of the inner localized electric field tend to be the maximum produced by even multiple widening. The distribution characteristic above provides instructions for quantization effect mechanism and the intrinsic formation factors of discrete transmission spectra of photonic crystal quantum potential well, and for applied designing of quantum optics devices.