An ATM switch includes a first stage, a second stage and a third stage each of which stages includes at least one basic switch, wherein the first stage, the second stage and the third stage are connected. The basic switch includes a part which refers to time information written in a header of an input cell and switches cells to an output port in an ascending order of the time information. In addition, the ATM switch includes a cell distribution part in the basic switch of the first stage. The cell distribution part determines a routes of a cell to be transferred such that loads of routes within the ATM switch are balanced. The ATM switch further includes an adding part which adds arriving time information to an arriving cell as the time information.