There are provided a system on chip (SoC) with a low power mode and a method of driving the SoC, the SoC including: a power part supplying a main clock signal and controlling analog and digital power supply at a normal mode and supplying a sub clock signal and turning analog power off at a low power mode; a radio frequency (RF) part generating the main clock signal at the normal mode and stopping operation at the low power mode, under the control of the power part; and a control part operating according to the main clock signal at the normal mode and operating according to the sub clock signal, under to the control of the power part.