Abstract: The development of the the MWIR/ LWIR dual color quantum well infrared FPA with the architecture switching between MWIR and LWIR was reported. The architecture including chip and read-out circuit (ROIC) frame was specially designed to realize the selection and switch of the MW band and LW band. The QWIP FPA key technologies such as quantum well material epitaxy, chip preparation and ROIC were described. The dual color 25 m pitch 384288 QWIP FPA is realized with the excellent noise equivalent temperature difference (NETD) of 28 mK in the MWIR and 30 mK in the LWIR at a operating temperature of 70 K. The peak wavelength is 5.1 m for MWIR and 8.5 m for LWIR. The infrared image of the target at room-temperature demonstrates the dual color detection function of the FPA.