Abstract: A developing device of this disclosure has: a housing, a developing roller, a developer conveying path, a partition board, a second communication path, a developer receiving port, a first conveying member, a second conveying member, and a conveyance capability inhibition part. A toner is cyclically conveyed in a first conveying path and a second conveying path. A first stirring screw is disposed in the first conveying path and driven into ration around a first rotation axis for toner conveyance. Formed downstream of the first stirring screw by the conveyance capability inhibition part is a toner accumulation part, and the amount of toner refilled from a toner refill port is adjusted. Where an aperture area of the first communication path is A1 and a circular area formed by an outer circumferential edge of the first stirring screw in section orthogonal to the first rotation axis is A2, relationship 0.5×A2<A1<1.2×A2 is satisfied.