In this study, we examined the influence of psychological pressure on the psychological, physiological, and behavioral aspects as well as performance in a sprint start. Fourteen university sprinters performed six 20-m sprint trials; three trials each in non-pressure and pressure conditions. The pressure was induced by the instruction of a cash reward for better performance, the threat of having to repeat the experiment in the event of worse performance, and evaluation of the sprint movement by biomechanics researchers. The visual analog scale (VAS), heart rate (HR), kinematic variables, and 20-m time were measured. Data analyses showed that the VAS and HR increased mildly by the pressure instruction. Significant negative correlations were observed between changes in HR and 20-m time and between changes in the 20-m time and maximum angular velocity of the knee joint. A significant positive correlation was observed between changes in HR and the maximum angular velocity of the knee joint. These results indicate that changes in physiological arousal and movement velocity induced by mild psychological pressure played a significant role in the sprint performance.