A power control device and method capable of reducing the power consumption of a DMB receiver according to whether or not CDM channels are received is provided. The power control device includes N CDM/FEC parts for demodulating a received broadcast signal into up to N CDM channel signals and error-correcting the demodulated channel signals and thereby generating a pilot payload signal and a transport stream, a plurality of clock switches for respectively turning on/off clock signals supplied to the N CDM/FEC parts, and a clock switch controller for controlling turning on/off of the clock switches, and controls supply of clock signals to the CDM/FEC parts according to CDM channel reception states, thereby making it possible to reduce the power consumption by the CDM/FEC parts.