A power amplification device includes a first power amplification unit having the positions of connectors thereof reversed, a second power amplification unit not having the positions of connectors thereof reversed, and a heat sink having a first flank thereof abutted on the heat radiation surface of the first power amplification unit, and having a second flank abutted on the heat radiation surface of the second power amplification unit. A transmitter using the power amplification device includes a plurality of power amplification devices, a distributor directly coupled to the input connectors of the power amplification devices, and a synthesizer directly coupled to the output connectors of the power amplification devices.