Color vision is sensitive to hypoxia and may degrade with altitude exposure. These effects may be clinically and operationally significant, especially for aircrew utilizing color multi-function displays. High-contrast visor HCV use may exaggerate these changes, as its use is known to distort color perception. The purpose of this research was to evaluate the effects of simulated altitude exposure on color vision and whether using the HCV would result in further degradation of color vision under these conditions. Following Institutional Review Board approval, a reduced oxygen breathing device was used to expose subjects with normal color vision to simulated cabin altitudes of ground level, 12,000 feet, and 8,000 feet. A computerized cone contrast test was used to assess color vision with, and without, the HCV at each simulated altitude. Utilizing 12 subjects, the results showed it was possible to demonstrate decreases in color vision between ground level and a simulated altitude in the absence of HCV use. The association depended on which cone S blue, M green, or L red was evaluated, with the S cone showing the greatest decrease at 8,000 feet. High-contrast visor use at simulated altitudes did not demonstrate a significant decrease in color vision.