Abstract: Response to the current is sensitive for risers and mooring systems in deepwater areas, so accurate derivation for the design current profiles is very important. This paper is based on the continuous 20 years of 1-hour current of a deepwater point in the middle South China Sea. Empirical orthogonal function and inverse first order reliability method are used to demonstrate the processes of derivation of extreme as well as fatigue design current profiles for deepwater structures. Comparison studies with the traditional and simplified methods are carried out to show the advantages of the proposed methods, which are expected to improve the engineering accuracy in real projects.