A image reading apparatus includes a first placement unit, a second placement unit, a first reading unit, a second reading unit, a rotating mechanism, and a switch-over mechanism that switches over the first placement unit and the second placement unit between a horizontal state and an inclined state. The rotating mechanism rotates the first reading unit and the second reading unit, so that, in the horizontal state, the first image reading unit and the second image reading unit read a medium placed on the first placement unit and a medium placed on the second placement unit respectively, and, in the inclined state, the first image reading unit and the second image reading unit read a medium placed on the second placement unit and a medium placed on the first placement unit respectively.