Troponin I（TNNI） is a member of the multi-gene family of calcium-binding proteins and exists in different types of skeletal muscles. Under the action of calcium ion concentration, it controls contraction of muscle, affects diameter and type of muscle fiber, and then affects meat fiber development, muscle fat accumulation, muscle moisture content, shear force, tenderness, cooked meat rate, flavor and other meat quality traits. TNNI gene is also used to identify adulteration of meat products and to monitor the safety of meat production process. Therefore, this paper reviews the structure and function of TNNI gene and its effect and application on meat quality traits of livestock, so as to provide a reference for further study on its mechanism of affecting meat quality traits of animals and strengthen its application in practical production.