Abstract: A modified construct of testing fixture to improve hermetic seal is disclosed. The construct of the testing fixture comprises a cylindrical body, made of Kovar alloy, a ceramic bottom plate and a cover plate, together creating an internal cavity to accommodate an integrated device to be tested. Multiple connecting pins made of Kovar alloy are soldered into through holes on the bottom plate. The integrated device to be tested is loaded up and placed into the cavity of the cylindrical body, and then a cover plate is used to seal off the opening and to make the connecting pins contact the integrated device to establish signal connection with the internal circuits of the integrated device. The modified construct of the testing fixture is able to keep the integrated device hermetically sealed during circuit testing, thus preventing water vapor and dust from getting in.