Underwater rock throwing is a common measure to prevent erosion and damage to riverbank embankments, and accurate detection of its distribution and volume is crucial. However, the construction difficulty of water area survey is high, there are many uncertain factors, and factors such as water flow interference may make it difficult to guarantee the survey effect, which seriously hinders the detection and control of construction quality and measurement. Practice has shown that selecting appropriate technical methods and instrument parameters based on specific engineering backgrounds, determining identification markers for rock throwing, and conducting reasonable and accurate data processing and interpretation are key to underwater rock throwing survey work. The selection of survey method combinations, on-site work techniques, criteria for determining the interface of the stone throwing layer, and key technical links such as data processing and comprehensive interpretation were focused on, based on the comprehensive survey of a water area reinforced with stone throwing at the foot of a certain embankment in Qiantang River. The comprehensive survey effect was evaluated by combining the results of drilling and various geophysical methods. The survey shows that a comprehensive technical method combining geophysical exploration and drilling, mainly based on shallow stratigraphic profiling, can effectively ensure the quality of underwater rock throwing survey by leveraging the advantages of various methods.