This paper presents a low profile high-efficiency transmitarray (TA) antenna based on a hybrid frequency selective surface (FSS). The hybrid FSS consists of two types of unit cells that have different incident angles and TE/TM polarization. This design minimizes the performance degradation caused by the oblique incident angle when designing a low profile TA antenna. In addition, the set of transmission phases to minimize transmission loss is selected by employing the optimal output phase reference. To verify its feasibility, a low profile TA (focal length/diameter of FSS =0.24) antenna that employs a unit patch antenna with a low gain and wide beamwidth as a feed antenna without an additional structure is designed. The simulated and measured results are in good agreement. In particular, the high simulated and measured aperture efficiencies of 42.7% and 41.9%, respectively, are obtained at 10GHz, respectively.