The traditional ocean pile design and calculation methods do not take the seabed instability into account, therefore, the accuracy and reliability of results can not be guaranteed, which will induce that the ocean buildings are not safe enough. So, the seabed instability shall be considered in the pile design and analysis. This paper firstly introduces the mathematical model of the pile-soil interaction considering the seabed instability based on Biot consolidation theory and fictitious pile technique, the soil pressure obtained through which can consider such conditions as ocean environment, seabed soil and pile etc. And then, based on the numerical solutions, this paper discusses the effects of pile top deflection, wave height, water depth and soil modulus on soil pressure, and some conclusions are obtained, which can be referenced in the design of ocean pile.