Numerically validated models are frequently used in the analysis of hydrodynamic responses and mooring line tensions of offshore floating platforms. This approach is very useful especially where access to laboratory facility is a challenge, or the limitation of available wave tank dimensions poses a great constraint to allow for proportionate scaling down of water depth. Thus, the numerical validation of a turret moored FPSO operating in a water depth of 1829 m is presented in this paper. The numerical model was developed in MAXSURF and perfected in DesignModeler. Time-domain coupled analysis was conducted in ANSYS AQWA over a simulation period of 12000 sec using a time step of 0.02 sec. All AQWA model analysis results including static offset, free decay, platform response and line tensions compared reasonably well with the published simulation (WINPOST) and experimental (OTRC) results. The variation recorded in AQWA results might be due to non-uniformity in FPSO hull geometry, possible mismatch in the prediction of wind and current coefficients, and the non-inclusion of hull viscous effect in the numerical simulation. The mooring tension spectrum generally compares very well. The close agreement of the validated model with published results indicated proper modelling of the referenced FPSO platform. Hence, the validated model can be used as a benchmark for further studies concerning hydrodynamic responses, mooring line tension, and restoring behavior of a turret mooring system. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.