A development device includes a housing for containing developer, a developer bearer to carry by rotation the developer contained in the housing to a development range position facing a latent image bearer, and developer conveyance device that includes a rotary shaft, a conveyance blade extending axially along the rotary shaft, projecting from the rotary shaft, and extending obliquely to the rotary shaft, to transport developer as the rotary shaft rotates, and a flexible agitation blade provided to the rotary shaft. An axial range of the flexible agitation blade overlaps at least partially with that of the conveyance blade. The flexible agitation blade has a width wider than a width of the conveyance blade and extends beyond an outer edge of the conveyance blade in the direction of diameter of the rotary shaft.