A non-profiled (rectangular) plate section was investigated for its effect on the performance of a flapping wing turbine for power generation. The plate was subjected to laminar flow conditions having a steady free stream flow (Reynolds number Re 1100); while flapping with prescribed sinusoidal pitching and plunging kinematics. Results of numerical simulation give a power efficiency as high as 34% for a non-profiled plate with a pitching amplitude of 75º, a plunge amplitude of 1 chord, a phase difference of 90º between pitch and plunge, a reduced frequency 0.8, at pivot location 1/3 chord from the leading edge. This performance is 5.35% over that of the profiled counterpart (NACA0012). Results also show that similar to the profiled plate, the plate thickness has an insignificant effect on the turbine performance.