A closed cycle MHD (CCMHD) single power generation system without any conventional gas turbine and steam turbine power generation systems is proposed as one possibility of highly efficient power plant. On the basis of preliminary calculations, the total plant efficiency of the CCMHD single system can reach 60%, which is comparable to that of the CCMHD system combined with conventional bottoming power generation systems. The exclusion of the bottoming systems requires a high performance heat recovery system working for relatively high temperature. The CCMHD single system proposed here is worth examining in more detail.