Recent developments in turbine technology allow the extraction of kinetic energy from tidal flows. This method of renewable energy generation is gaining popularity because of the high predictability of tides, the low environmental impact with no land occupation, and the lower investment needed for tidal turbines. In the present study, an existing three-dimensional finite element numerical model was refined to include an algorithm for computing the power density and mean power density around Kinmen Island of Taiwan. The refined model was validated against measured water levels and tidal currents at different gauging stations. The model results are in reasonable agreement with the measured data. The validated model was then used to assess the potential tidal current energy resources, including the distributions of power density at the mid-flood and mid-ebb of a mean spring tide and the mean power density. Three potential points at the east and west coasts of Kinmen Island were evaluated. The tidal current and corresponding power density at these points were computed with the model for a 15-day period to cover the spring-neap tide cycle. The annual energy output was obtained based on the power density curve to be numerically integrated. In light of the topographic considerations, the integration of the power supply, and the existing harbor/port facilities, the location near Suetau would be an appropriate site for establishing a tidal current power plant.