A power amplification apparatus, a remote radio unit, and a base station are provided to improve power amplification efficiency. The power amplification apparatus includes an envelope modulator, a main power amplifier, and a first auxiliary power amplifier. The envelope modulator is configured to obtain an envelope voltage based on a received envelope signal and output the envelope voltage to the drain of the main power amplifier. The main power amplifier is connected to the envelope modulator and configured to use the envelope voltage as an operating voltage, and is connected to the first auxiliary power amplifier, to output the envelope voltage to a drain of the first auxiliary power amplifier. The first auxiliary power amplifier is configured to use the envelope voltage received from the main power amplifier as an operating voltage.