To meet the requirements of satellite communication (SATCOM), in this paper, a wideband high stability transmitarray antenna (TA) for SATCOM is proposed. The TA is composed of 225 metal-only unit cells that comprise three metallic layers with an air spacer in between. High stability is capable by adopting a simple metallic square loop and two pairs of orthogonal stubs with a 1 mm thickness of the layer, which ensures lower assembly complexity and higher integration. The proposed unit cell can also support linear polarization (LP) wave excitation and circular polarization (CP) wave excitation simultaneously. Meanwhile, the metal-only unit cell can operate without dielectric loss, which leads to higher working efficiency. By adjusting feature sizes, eight different kinds of the unit cell are designed to realize a 3-bit TA which enables obtaining a gain of 23.53 dBi. Finally, four TA prototypes have been fabricated and tested successfully. The measured result shows a 28.5% 3 dB gain bandwidth from 30 GHz to 40 GHz, which is in good consistency with the simulated design. This compact and mechanical robustness design provides an alternative proposal for SATCOM.