The evaluation of the underwater riprap effect for the riprap revetment project is the key and difficult point of the underwater quality control of the project. Accurately grasping and analyzing the underwater quality status of the project has played an important role in ensuring the construction quality of the riprap revetment project. GIS （geographic information system） technology has powerful spatial data processing and analysis capabilities，which can be used for multi-dimensional qualitative and quantitative analysis of the underwater riprap effect.The analysis results can accurately evaluate the construction quality and guide the next stage of construction，and reduce construction costs. By the analysis of the three test areas，we summarize the general construction rules：1） The upstream start in the project area and the deep water side of the downstream are prone to scour，and the riprap effect is poor. 2） The riprap effect of the middle in the project area and the near-shore area is better，but these areas are also prone to excessive construction.