Abstract: An image processing method of solving the problem of the interference caused by the edge features of road markings lines when recognizing road boundaries by edge detection was proposed. The results detected by the edge detection algorithm were used to process gray road image line by line. The gray values near the point where edges pass by the line were determined and modified to reduce the edge features of road marking lines while retaining the edge features of real boundaries of the road. Additionally, a road boundary recognition system based on edge detection was built to test the method. The validity and real-time performance of the proposed method were verified by using more than 130 road images as input. Experimental results show that the proposed method can effectively eliminate the interference of road marking lines on road boundary detection techniques based on edge detection.