A speaker device of the present invention roughly comprises a cabinet (1) and a speaker unit (2a). The speaker unit (2a) is attached to an opening portion formed in a front surface of the cabinet (1). The speaker unit (2a) has a back surface frame (3a), a front surface frame (4a), a first magnetic circuit (5a), a second magnetic circuit (6a), an edge (7a), a damper (8a), a diaphragm (9a), a voice coil bobbin (10a), and a voice coil (11a). A non-magnet member (91a) which is a portion of the diaphragm (9a), the first magnetic circuit (5a), and the second magnetic circuit (6a) play a role as a negative stiffness mechanism to suppress an influence of an acoustic stiffness, thereby achieving a small-size speaker device capable of reproducing low-frequency sound.