A semiconductor memory apparatus and refresh control method are presented. The semiconductor memory apparatus includes a memory cell block composed of a multiplicity of floating body cell (FBC) transistors. Each FBC transistor has a gate connected to a word line, a drain connected to a bit line, and a source connected to a source line. FBC transistor pairs are formed by sharing the source lines in the plurality of the floating body cell transistors. When a refresh signal is enabled, the semiconductor memory apparatus is configured to read data stored in the memory cell block by enabling a refresh read signal and then configured to rewrite the read data in the memory cell block by enabling a refresh write signal.