The Support Laboratory of Nanofabrication of Yamaguchi University is a member of the Nanofabrication Platform Consortium in the Nanotechnology Platform Japan. Our laboratory features the desorption gas analysis of materials and devices based on the original vacuum technology in addition to the nanofabrication. In this paper, an operand desorption gas analysis system (apparatus for dynamic thermal desorption spectroscopy), which is one of our gas analysis systems, is explained. The advantage of this system is that it enables a desorption gas analysis of an operating device under an approximately atmospheric pressure (0.1 to 0.2 MPa) using gas chromatography/mass spectrometry, in contrast to a sample placed in a vacuum in a conventional apparatus for thermal desorption spectroscopy. Moreover, two measurement examples (DC electric motor and solar cell) using this operand gas analysis system were described. In the DC motor, the main desorbed gas from the motor behaved similarly to the motor electric power with the occurrence of failure or stop caused by heating. In the solar cell, from the comparison of the temperature dependence between the open circuit voltage and the main desorbed gases from the solar cell, the temperature durability of the sealing part is confirmed to be related to the electron generation efficiency.