The invention relates to a device and method for maintaining lateral lying sleeping of the human body. The device comprises a prone position identification assembly which is electrically connected with an electric appliance driving assembly, and the electric appliance driving assembly is electrically connected with an awakening assembly. A prone position information processing assembly is further arranged between the prone position identification assembly and the electric appliance driving assembly. The invention further comprises the method for maintaining lateral lying sleeping of the human body through the device for maintaining lateral lying sleeping of the human body; when the human body lies on his back or lies on his stomache, the gestures are instantly identified through the prone position identification assembly; the prone position identification assembly directly sends a command to the electric appliance driving assembly, or a command is sent to the electric appliance driving assembly through the prone position identification assembly; and after the electric appliance driving assembly receives the command, the awakening assembly is instantly driven to awaken the human body, and a user maintains lateral lying; or a motor of a body turning bed is driven to achieve lateral turning of the turning bed, so that body turning to lateral lying of the human body is achieved. By means of the device and method, poor sleeping postures of the human body can be corrected in time, full-process healthy sleeping postures of the human body are maintained, and snoring and sleep apnea are prevented.