The stress field induced by waves in seabed is calculated on the basis of Biot’s two-dimensional consolidation theory. On the assumption that cohesive force of seabed soil isn’t associated with wave action

a criterion is proposed for discriminating wave-induced failure in seabed of feebly cohesive soil or silt; and it enriches traditional discriminant methods. Moreover

with a detailed discussion about influence of cohesive force on failure depth of seabed

the criterion is applied with ideal results to analyze the stability of seabed in the sea area of Chengdao Oilfield

the yellow River Delta. In the analysis

influence of cohesive force of soil on failure depth of seabed induced by waves is discussed under two oceanic conditions (with occurrence periods of 50 and 5 years). Calculation results show that the cohesive force of soil has a prominent influence on seabed stability.