Abstract: Many soil properties with much fuzzy and uncertainty influence the seabed liquefaction, and the liquefaction mechanism is very complex. In this article, the fuzzy method was used to analyze the seabed liquefaction. The fuzzy comprehensive evaluation model of seabed liquefaction degree was established, and the main parameters that influence liquefaction were analyzed. According to the pore pressure variation during liquefaction, the liquefaction was divided into four degrees. The liquefaction degree of Cheng Dao Sea seabed of Yellow River estuary was evaluated by fuzzy comprehensive method, and the result shows the liquefied state. Under wave of a case of 50 years, the soil at most area ofⅠ district and Ⅱ district don’t liquefy, in Ⅲdistrict most area of soil liquefy, and in Ⅳ district soil liquefy. Finally, the results by fuzzy comprehensive method and simple empirical method compared, the two results are consistent, which shows the fuzzy method is feasible in seabed liquefaction degree evaluation.