To provide an image forming apparatus and a toner supply device capable of smoothly opening/closing a toner discharge port as well as suppressing toner scattering.

An image forming apparatus 100 is provided with: a toner supply device 300 including a toner storage section 301, an opening formation section 302 forming a toner discharge port 3021, a shutter section 303, a first engaging section 304 fixed to the toner storage section 301, and a second engaging section 305 fixed to the shutter section 303; a supporting member 400 for rotatably supporting the first engaging section 304; and a movement restriction member 500 for restricting the movement of the second engaging section 305. The second engaging section 305 and the movement restriction member 500 are engaged more outside than the toner storage section 301 in the direction of the central axis line S₁ of the first engaging section 304 and the shutter section 303 is moved to the toner discharge port 3021 when the first engaging section 304 rotates.