A frequency synthesizing apparatus and method for a multi-band radio frequency (RF) receiver is provided. The frequency synthesizing apparatus includes a simple circuit configuration with a single SSB mixer and thus, may synthesize six high frequency signals. Signals to be inputted into the SSB mixer include a first signal and a second signal. The first signal is generated based on a VCO and a PPF. Also, the second signal is selected from a plurality of frequency divided signals which are generated by dividing a signal generated in the VCO via a plurality of dividers.