The interchange diversion section of tunnel necessitates enhanced luminance for safety reasons, thereby creating a transition from a lower luminance area (base section) to a higher luminance area (enhanced section), known as the uneven lighting environment. This transition may adversely affect drivers’ visual recognition of guide signs. To investigate the impact of this uneven lighting environment on the distance at which drivers recognize guide signs, a static visual recognition test was conducted on the guide signs in the interchange diversion section under the uneven lighting conditions of tunnel. The findings indicated that the uneven lighting environments significantly influenced the visual recognition distance of guide signs. By fitting the 85th percentile of visual recognition distances under different uneven lighting environments, a model of visual recognition distances under different uneven lighting environment brightness settings was created, and based on the model, the safety of uneven lighting environment settings under different design speeds was evaluated.