In the textile process, control the yarn tension is very important. Tension-meter is equipped with three pulleys wheels. These pulley wheels can measure and read tension of yarn easily and fast under dynamic state. It is also used to measure tension of electrical wire and metal wires. Tension-meter rotating parts are constituted of sapphire axletree, and equipped with a damper. It can completely eliminate self-vibration and the resistance caused by instrument itself. At last, it enhanced reliability of the result reading.