This special issue gives a comprehensive discussion of Micro Devices and Microsystems of Brain Computer Interface in the following key points: Neural Microelectrode Array, Microchips for Detection and Stimulation, Deep Brain Stimulation. Related papers with yearly progressive increase indicates that Micro Devices and Microsystems of Brain Computer Interface as promising micro- and nano-sensor technologies are of great interest. Thus, it is extremely important to promote the development of Novel Devices and Microsystems of Brain Computer Interface. We hope our readers enjoy finding out about work being done in the field of Micro Devices and Microsystems of Brain Computer Interface in Microsystems and Nanoengineering.