Objective To investigate the immediate impact of changes in kinematic and dynamic characteristics before and after visual intervention on the gait of hemiplegic patients. Methods Thirty visually normal hemiplegic patients were recruited. Recruit 30 hemiplegic patients with normal vision, select plane mirrors with different refractive degrees (0°), concave lenses (+150°, +450°) to simulate normal vision, moderate myopia, and high myopia scenarios for straight line walking tests. The Qualisys 3D motion capture system and Kistler 3D force platform were employed to collect kinematic and dynamic parameters of the patients, and the differences in related indicators before and after visual intervention were compared.Results Visual intervention affected the step length, walking speed, and joint angles of hemiplegic patients. Especially after acute changes in vision, there is a significant difference in the stride length and ankle joint angle on the patient's affected side.. Under high myopia, step length and step length symmetry were better than under moderate myopia, but at the expense of gait speed. Visual intervention led to asymmetric trends in step length symmetry and joint angle symmetry. There were very significant differences in COP and COP symmetry between normal vision and high myopia.Conclusion Acute changes in vision can significantly affect the gait of hemiplegic patients, especially when there is a notable decrease in walking speed and changes in ankle joint angles with high myopia, and an increase in walking speed with moderate myopia. Additionally, under all conditions of vision change, the symmetry of COP is reduced, indicating a higher risk of falls. This suggests that during the rehabilitation process of hemiplegic patients, reasonable vision assessment and corresponding intervention measures are expected to improve the patient's walking ability and quality of life.