Quantum-dot Cellular Automata (QCA) lead to fundamental changes in nanoscale technology. It promises small area, low power, & high-speed structures for digital circuit design. This paper presents efficient low power structures of reversible multiplexer & demultiplexer (RMD) modules based on the QCA technology. The simulation result shows that the proposed RMD module has utilized less area & low power consumption. The simulation, layout, & energy dissipation of the proposed RMD module have been carried out using the QCA Designer-E simulation tool.