The growth and fabrication of a 320×256 type-Ⅱ InAs/GaSb superlattice long wavelength infrared focal plane array detector were reported. The superlattice material was grown on GaSb substrate using molecular beam epitaxy (MBE) technology with a PBIN structure. The structure of infrared absorption layer is 14ML (InAs)/7ML(GaSb), the focal plane array had a pixel size of 27μm×27μm and a pitch of 30μm. The device fabrication process consisted of mesa dry etching, side-wall passivation, metallization and flip-chip hybridization with readout integrated circuit (ROIC). At 77K, the detector had a 100% cut-off wavelength of 10.5μm, and a peak detectivity of 8.41×109cmHz1/2W-1. Concept proof of infrared imaging was also demonstrated with the focal plane array at liquid nitrogen temperature.