For extracting the road and navigation line under the shadow environment, a road and visual navigation line extraction algorithm is proposed based on illumination invariant image segmentation and vote functions. The color illumination invariant image is acquired with orthogonal decomposition method. After the image segmentation, the road region is extracted through the structure of the vote function and road criterion. The navigation line is detected by scanning path location and the least squares fitting. The proposed method does not require a large number of samples to learn. Experimental results show that, compared with two existing algorithms, the proposed algorithm has obvious advantages in detection accuracy, speed and complexity, it can effectively solve the road and navigation line extraction under the shadow environment.