A method of controlling power supply for amplifying a radio frequency (RF) signal includes: determining whether a power supply mode for supplying power from a power modulator of a communication apparatus to an amplifier for amplifying the RF signal is an envelope tracking (ET) mode for supplying power based on ET of the RF signal; when the power supply mode is the ET mode, determining whether a downlink block error rate in the ET mode and a downlink modulation method in the ET mode satisfy a first condition; when the first condition is satisfied, determining whether a full resource block (RB) in an uplink band is allocated to uplink data transmission; and when the full RB in the uplink band is allocated to uplink data transmission, switching the power supply mode to an average power tracking (APT) mode for supplying power based on average power of the RF signal.