Abstract: After years' practice, offshore riser installation has been a proven technology, but most of the operations still rely on large-scale offshore crane vessels. In this paper, one engineering project in the South China Sea was taken as an example to propose a new riser installation method on the basis of traditional riser installation technologies. In this new method, a small-size saturation diving support vessel is used to install risers. Then, the construction plan of dual-crane uprighting riser installation was introduced in details. Finally, dynamic simulation and analysis was conducted on the riser installation process by using the software Orca Flex so as to provide the effective check basis for the design of construction plan. The application of this new method decreases the quantity of operation vessels, reduces the operation cost effectively and improves the operation efficiency. The research results is of great significance to the development of oil and gas fields.