The performance of an Archimedes spiral turbine (AST) for hydrokinetic applications was examined using a three-dimensional unsteady numerical model utilizing the six degrees of freedom (6-DOF) solver that is available in ANSYs Fluent software. From the computational fluid dynamics (CFD) simulations, the power coefficient (Cp) curve was estimated. This curve was compared with the curve of an Archimedes screw hydrokinetic turbine (ASHT) reported in the literature. The ASHT was found to be more efficient than the AST for electricity generation. The highest value of Cp for the AST was 0.337, which is a relatively high value in comparison with that of other types of hydrokinetic turbines. The results calculated from the CFD for the AST were compared with an experimental study reported for wind applications.