In the development of Dewar for packaging long-wave QWIP-LED quantum well detectors,a structure for encapsulating long-wave QWIP-LED quantum well infrared detectors is elaborated.Dewar uses a side-cover design with optical signals from the infrared.The Light signals enter from the infrared window and pass out from the near-infrared window.A method is proposed in which the detector is glued to the pipe socket,and the pipe socket is screwed to the cry cryogenic platform as a whole,thereby improving the interchangeability of the detector and reducing the design by thermal adaptation.To reduce the influence of Low-temperature stress on the detector,TC4 material with low-temperature loss is selected to reduce Dewar heat leakage.Through the breakthrough of these key technologies,the long-wave QWIP-LED quantum well detector Dewar component has been successfully developed.The performance index of Dewar is up to the standard,the imaging effect is good,which meeting the requirements of engineering applications.