The purpose of shipping risk early-warning is that some effective measures are taken to reduce risk probability before the risk brings heavy loss. The shipping risk has the dynamic characteristic, so the key of early-warning is to choice risk early-warning index correctly and evaluate risk grade quantitatively. According to the element extension theory, the rhombus inference model is applied to establish the index system. And the problem of risk grade evaluation can be solved by the assessment model of multi-index performance parameter, which is developed by the extension engineering method. Finally, the main shipping risks and their grades are identified by the example analysis based on the statistical data, which shows the effective and feasible of the shipping risk early-warning method. © 2011 Shanghai Jiaotong University and Springer-Verlag Berlin Heidelberg.