Subgrade deformation is one of the main causes of highway disease, and its hidden dangers in the process of highway construction, management, operation and maintenance are increasingly prominent. At present, the relevant technologies represented by remote sensing mapping, geophysical exploration and multi-sensor have played an important role in subgrade deformation testing. In order to study the dynamics and development trend of road engineering field, and sort out the research status of theory, method, technology and equipment in road engineering field in recent years, the main forms and influencing factors of roadbed deformation were expounded, the types of roadbed deformation testing technology and their advantages and disadvantages were analyzed, and the understanding and development trend of the whole cycle intelligent monitoring system was further discussed. The construction of subgrade deformation monitoring system was the main way to perceive the state of subgrade, evaluate the stability of subgrade and forewarn the disaster. With the rapid development of artificial intelligence and advanced testing technology, the testing technology of subgrade deformation presented new characteristics such as dynamic, transparent and intelligent. It is an important development direction of road safety operation and maintenance in the future to strengthen the research and development of test theory, technology and equipment and form a multi-means subgrade health monitoring system based on three-dimensional space.