Taking the 300 000 ton-class oil terminal engineering of catfish bay in Dalian Port as an example, this paper analyzes the solution for the problem that the largest depth of semi-submersible barge could not meet the request of floating stability of large-scale caisson. A comparison with the method of 300 000 ton-class oil terminal engineering in Yingkou port is made. The result shows that the technology of semi-submersible barge shipping large-scale caisson assisted by crane ship is feasible. This method is an improvement of the original shipping technology for the large-scale caisson and had broadened the appliance field of the semi-submersible barge shipping large-scale caisson.