The integrity bchavior and life of a bolted joint depend a great deal upon the clamping force exerted by the bolts on that joint, Too high or little clamping force can lead to fa-tigue failure, damage or leaks, vibration loosening, slipping a nd cramping. As a result many efforts have been made to solve the problem [1], [2], [3], We have developed a system that tests thestress from it. The influence of temperature within the range of 20-360℃ is au-tomatically compensated. This equipment not only can moni-tor the stress during its assembling, but also at high tempera ture and will alarm when the bolt stress has serious changes, This alarm can win some time for us to take emergency measures to avoid disasters.