a first roller pair including a first roller and a second roller, the first roller pair being configured to transit between a contact state in which the first roller and the second roller are configured to convey a sheet by coming into contact with each other, and a separated state in which the first roller and the second roller are separated from each other;

a first driving unit configured to drive the first roller pair;

a second roller pair disposed downstream of the first roller pair in a conveyance direction of the sheet;

a second driving unit configured to drive the second roller pair;

an image forming unit disposed downstream of the second roller pair in the conveyance direction and configured to form an image on the sheet; and

a control unit configured to execute a first mode in a case where a thickness of the sheet is a first thickness, and configured to execute a second mode in a case where the thickness of the sheet is a second thickness thinner than the first thickness,

wherein the second mode includes (1) a first processing of controlling the first driving unit and the second driving unit such that rotational speeds of the first roller pair and the second roller pair become a first rotational speed, and of conveying the sheet to the second roller pair by the first roller pair which is in the contact state, (2) a second processing of transiting the first roller pair from the contact state to the separated state, and (3) a third processing of controlling the second driving unit such that the rotational speed of the second roller pair is decelerated from the first rotational speed to a second rotational speed less than the first rotational speed, and of controlling the first driving unit such that the rotational speed of the first roller pair becomes faster than the second rotational speed,

wherein the first mode includes (1) a fourth processing of controlling the first driving unit and the second driving unit such that the rotational speeds of the first roller pair and the second roller pair become the first rotational speed, and of conveying the sheet to the second roller pair by the first roller pair which is in the contact state, (2) a fifth processing of transiting the first roller pair from the contact state to the separated state, and (3) a sixth processing of controlling the second driving unit such that the rotational speed of the second roller pair is decelerated from the first rotational speed to the second rotational speed, and of controlling the first driving unit such that the rotational speed of the first roller pair is decelerated from the first rotational speed to equal to or less than the second rotational speed.