An image forming apparatus includes a rotatable image bearing member; an exposing unit, including a first passing portion for passing light, for exposing the first image bearing member through the first passing portion; a first developing device, disposed opposed to the exposing unit, for forming a toner image on the basis of an electrostatic latent image formed on the image bearing member by an image exposure; an image heating device, disposed above the exposing unit with respect to a vertical direction of the image forming apparatus, for heating the toner image formed on a recording material using heat; a first wall portion disposed between the first developing device and the first passing portion; and first airflow forming means for forming an airflow along a rotation axis of the image bearing member, in a space formed by the first developing device, the exposing unit, and the first wall portion.