With the development of human society and the deepening and expansion of scientific research, chronobiology has been widely introduced into the field of sports science; the majority of scientists, coaches and athletes put more and more emphasis on research of the movement time, and pay attention to the relationship of sports and human biological rhythms. This article studies gymnast’s athletic ability from the perspective of human biological rhythms. In the paper it first establishes the macroscopic and microscopic biorhythm mechanism model according to the rhythm characteristics of organisms, and analyzes the significance of the parameters in the mathematical model, then analyzes the circadian rhythm characteristics that presented by gymnast’s heart and lung function indicator, blood and vital energy indicator, provides a more scientific reference for gymnastics strategy, finally analyzes the index reflecting the ability of gymnast’s body function, and analyzes the biological rhythms characteristic of the hormone levels that can reflect the gymnast’s muscle strength, speed, endurance and the ability of stress from the side. Through the analysis methods and results of the mathematical models and experimental data established in the text, it provides more scientific strategies for training and competition arrangements of gymnastics, meanwhile provides a theoretical basis for the study of biological rhythms characteristic.