The present invention has been made to provide a sensor device (1) capable of surely measuring such as a deformation amount of a measuring object, and the sensor device (1) in the present invention includes a sensor element (2) having a sheet-like dielectric layer (11) comprising an elastomer composition, and electrode layers (12A, 12B) comprising an electro-conductive composition containing carbon nanotubes and formed on a top surface and a bottom surface of the dielectric layer (11) to be at least partially opposed to each other across the dielectric layer (11), in which an opposed portion of the electrode layers (12A, 12B) serves as a detection portion, and the dielectric layer (11) is reversibly deformed to change an area of its main surface a converter (3) electrically connected to the sensor element (2) and configured to convert capacitance at the detection portion varying in accordance with the deformation of the dielectric layer (11) to electric characteristics, and an output unit (4) configured to output information corresponding to the electric characteristics in a form recognizable by any of the five senses.