To miniaturize a hinge with a thermo-actuator used in a ventilation device opening and closing a ventilation port, with a simple structure, and to rotate the thermo-actuator with small motion.

This hinge 10 with the thermo-actuator comprises: two sheets of hinge members 12, 13 relatively rotatably journaled to a spindle 11; a spring means 14 for giving rotating habit to one direction to the hinge members; and the thermo-actuator 20 operated in accompany with temperature change for rotating the hinge members against energizing force of the spring means. The thermo-actuator is provided with: a rod member 34 linearly moved in accompany with advancing and retracting motion of the thermo-actuator; and a lever 41 engaged with the rod member 34 for converting the linear motion into the rotating motion, and having hinge engagement portions 44, 44 for rotating two sheets of hinge members against the energizing force of the spring means. The hinge engagement portions of the lever are engaged with engaged faces 17, 18 formed on basic end side portions of the two sheets of hinge members to rotate the hinge members in the other direction.