In a railcar truck in which secondary springs are disposed between the railcar truck and a carbody of the railcar, the railcar truck has a pair of side beams having concavities configured to receive the secondary springs. Each of the side beams has a side beam outer wall, a side beam inner wall, a side beam lower wall and a side beam upper wall, and the side beam upper wall includes an opening through which the received secondary spring projects. The concavity is formed by the side beam outer wall, the side beam inner wall and the side beam lower wall, and receive the secondary spring through the opening.