A process unit is described. The process unit may include a unit main body being detachably mountable to an image forming apparatus main body and having a developer carrier for supplying a developing agent to an image carrier on which an electrostatic latent image is formed, a toner box being detachably mountable to the unit main body and accommodating the developing agent, a pivoting member pivotably disposed at the unit main body, and a contacting member disposed at the pivoting member and contacting with the toner box from a downstream side in a detaching direction of the toner box from the unit main body.