This study investigated how the human body responds to visual sensory information in upright standing. Our efforts were focused on using a linear system identification approach in which the input was the position profile of the visual perturbation through virtual reality, and the output was the body angle through measuring the hip displacement. The results unveiled that the underlying system acts as a band-pass filter over the frequency range of interest. The findings demonstrated that by increasing the amplitude of the perturbations, the gain between the body angle output and the visual input decreased, indicating a nonlinear behavior. Also, the continuously diminishing phase of the frequency response revealed the presence of a delay of 150 ms for visual contributions. Additionally, a new detrending method using the Fourier Transform was implemented to remove nonstationarities, achieving a more accurate model. Moreover, an initial investigation showed a significant distinction in responses to the presented visual input between the two groups of subjects.Clinical Relevance- The proposed research offers insights into complex underlying mechanisms of human postural control in the presence of visual perturbations. Consequently, this study has the potential to contribute to the rehabilitation process for patients with balance disorders due to visual sensory impairments by re-educating or emphasizing more on the visual sensory modality.