This chapter explores the existing application of magnetorheological elastomer (MRE)-based devices which have been proposed in several field applications. It covers the design parameter and general performances of the devices. Some applications which have been published through patents as well as scientific articles were highlighted in the last two decades. The working principle and prototype performances are also delivered. We classify practical applications into three areas of semi-active, active, and sensory systems. However, the discussion is limited to the basic working principle of the device without further elaboration of their control strategies. This is because control systems in MRE-based devices have broad coverage. Besides, the fundamental technique in controlling MRE-based devices is similar to that of controlling MR-fluid-based equipment.