In this paper, a novel transmitting scheme for multiple-input multiple-output ( MIMO) satellite relay-based multi-user multi-beam communications is proposed. It is considered that multiple terrestrial relay nodes employ amplify-and-forward ( A-F) relaying and intend to improve the reliability and spectral efficiency of satellite radio links. Zero forcing ( ZF) and minimum mean square error ( MMSE) signal detection techniques are employed, which have been well-established in terrestrial wireless communication systems. Numerical results are provided to quantify the performance gain of the proposed system configuration in terms of the bit-error-rate ( BER) and the channel capacity.