This research studies the effects on the dynamic responses of a turret-moored FPSO with respect to the changes in the mooring lines� configurations that include pretension forces and azimuth angles as well as the changes in the water depth. Numerical calculation is carried out based on a time domain analysis using the computational fluid dynamics� software STAR-CCM+. The dynamic responses in the heave, surge and pitch motions are studied when the FPSO is subjected to an environmental conditions based on a 100-yr hurricane condition for the Gulf of Mexico (GoM). © 2016 Taylor & Francis Group, London.