Image liquid level measurement technology has the advantages of non-contact measurement, wide application range and small occupancy volume, etc. It has extremely broad application and development prospects in the fields of industrial, chemical and hydrological monitoring. With the improvement of image processing algorithms and the improvement of industrial cameras’ performance, the performance indicators of image liquid level measurement technology are also significantly improved. In order to further study the image liquid level measurement technology, the basic working principle, classification and research status are sorted out. Finally, the paper gives a perspective to the trend for the image liquid level measurement technology.