An image forming apparatus includes a switchback roller which switches between a normal rotation direction and a reverse rotation direction, first and second gear train for rotating the switchback roller in the normal and reverse rotation directions, respectively, a switching unit including a pendulum gear which is movable among a first engagement position where the pendulum gear is engaged with the first gear train, a second engagement position where the pendulum gear is engaged with the second gear train, and a disengagement position where the pendulum gear is not engaged with the first gear train and the second gear train. The switching unit is switchable among a first mode where the pendulum gear is held at the first engagement position, a second mode where the pendulum gear is held at the second engagement position, and a third mode where the pendulum gear is held at the disengagement position.