In order to meet the needs of realtime monitoring of roadwater depth, it is very important to use the appropriate measurement method to measure the depth of roadwater quickly and accurately. Different measurement methods directly affect the accuracy of water depth measurement and some measurement methods for the roadwater depth are summarized, which can be divided into contact measurement, noncontact measurement and image measurement. The contact and noncontact measurements mainly use sensor technology to convert water depth into electrical signals, nonelectrical signals to measure the water depth. Image measurement uses image processing technology to extract the water level in the image to measure the water depth indirectly, and gradually become a research hotspot. By analyzing and comparing the advantages and disadvantages of each method, it is found that each measurement technology has different applicability in different environments, and the image measurement can better adapt to different environments. Finally, the development trend of roadwater depth measurement technology is prospected.