A small thermal fuse relates to the technical field of thermal fuse, and includes a fixed shell, the middle of the fixed shell is fixedly connected with a first insulator. Both ends of the bottom of the fixed shell are fixedly connected with second insulators. A pin is fixedly connected to the second insulator, and a mounting groove is opened in the middle of the first insulator. An organic temperature sensor is arranged in the middle of the installation groove. A first spring is fixedly connected to the middle of the organic temperature sensing body, and the outer two ends of the organic temperature sensing body are fitted with conductive bodies. A second spring is just connected to the outer side of the conductor, and one end of the second spring away from the conductor is fixedly connected to the first insulator. By arranging the organic temperature sensing body and the first spring, the present invention can stably separate the two electrical conductors when the organic temperature sensing body is melted, and has the performance of efficiently isolating arcs and breaking current, and greatly improving safety performance.