The invention relates to a multiplexing method for visual guidance and a visual odometer. Guide wires with two alternating colors are provided in a moving path of a mobile robot. Wire information of the guide wires is extracted as visual guidance amount by a visual image processing while an alternating frequency of the red and white color is calculated, and thus the function of the visual odometeris achieved. The invention also provides a visual mileage calculation method and an odometer. The multiplexing method for visual guidance and a visual odometer is simple to be implemented, small in calculation amount, more suitable for engineering application and speed measurement of various carriers. According to the multiplexing method for visual guidance and visual odometer, the design cost isreduced based on the existing camera sensor mileage calculation. The displacement of the robot is determined when the wires with the two colors alternately occurs, so that the speed of the robot is determined without complex feature extraction and matching, and the calculation amount is reduced. In addition, the computational power requirement for the CPU is reduced, and the cost is further reduced.