An image forming apparatus includes a main body, a post-processing unit, a transport unit, a filter and a suctioning/exhausting unit. The post-processing unit is disposed adjacent to the main body. The post-processing unit performs predetermined post-processing on a recording medium on which an image is formed in the main body. The transport unit transports the recording medium from the main body to the post-processing unit. The suctioning/exhausting unit suctions air in the transport unit and exhausts the suctioned air through the filter to an outside of the main body.