An Ethernet switch with rate control and associated method is provided. Each port in the switch has individual settings of egress/ingress) rate control, which are stored in a register and configured based on required rates. The switch uses data volume that a port can output/input within each unit time to control egress/ingress rate of the port. Further, the egress rate can be precisely controlled by using uniform random numbers provided by an random number generator of the switch, and the ingress rate can be advantageously controlled by combining a proper kind of congestion control, which is performed according to the capability of a device connected to the port, such as full-duplex or half-duplex, and flow control.