Abstract: ［Objectives］The wind load has a great impact on the stability of FPSO, which is frequently calculated using the OCIMF rule for large tankers and the API rule for offshore platforms at present. However, due to the complexity of FPSO superstructure, whether these two rules can be applied to wind load calculation of FPSO needs further study.［Methods］This paper established a 300,000 ton class FPSO numerical model with universal superstructure. The wind load on FPSO in severe sea conditions under different wind angle is calculated, and compared to results by the rules. The shielding effect is analyzed as well as the heeling angle of FPSO.［Results］The maximum heeling moment and wind load under upright floating attitude appears at 270° wind angle. The heeling moment and wind load under heeling floating attitude are larger than those under upright floating attitude, and the maximum heeling moment appears at 10.5° wind angle under 280° wind angle; API and OCIMF rules’ results show a big difference compared with CFD, the difference between their results at 270° wind angle and CFD is 13.6% and 24.5% respectively.［Conclusions］The flow field details obtained by numerical simulation are conducive to analyzing the shielding effect between superstructures, which make the wind load predictions on the ship more accurate. This paper can provide some references for the stability design of FPSO.