Recently marine disasters and marine accidents have happened very frequently, bringing about great threats, which attracted great attentions of central and coastal governments on marine emergency affairs and it is necessary to formulate and update relevant local contingency plans. This paper takes Shanghai as the subject to study the determination of the hierarchies for provincial contingency plans of marine emergency affairs. Taking into account of practice by relevant coastal provinces, a conclusion can be drawn that no specific standards or guidelines for choice between sectoral contingency plans and special contingency plans. Nevertheless, local governments tend to determine the hierarchies for the plans in terms of the frequency and the threat of marine emergency affairs they faced or are facing. Most provincial governments adopt sectoral contingency plans for marine emergency affairs and formulate separate plans for different kinds of emergency affairs. When potential threats are increasing, it is, however, likely to upgrade or adopt the plans to special contingency plans.