A Doherty Power Amplifier, the Doherty Power Amplifier comprising a first amplifier and a second amplifier, the Doherty Power Amplifier further comprising: a first transmission device, comprising: - a first quarter wave length transmission line (TL d0), configured to couple a drain of the first amplifier and a drain of the second amplifier, and feed first even order harmonic components generated at the drain of the first amplifier to the drain of the second amplifier; - a second quarter wavelength transmission line (TL mp), configured to couple the drain of the second amplifier and an output terminal of the second amplifier; and - a third quarter wavelength transmission line (TL p), configured to couple the output terminal of the second amplifier and ground by connecting in series with a first capacitor (C 4), wherein the first even order harmonic components are shorted to ground through a signal path via the first quarter wavelength transmission line (TL d0), the second quarter wavelength transmission line (TL mp), the third quarter wavelength transmission line (TL p), and the first capacitor (C 4); and a second transmission device, comprising: - the first quarter wavelength transmission line (TL d0), wherein the first quarter wavelength transmission line (TL d0) is further configured to feed second even order harmonic components generated at the drain of the second amplifier to the drain of the first amplifier; - a fourth quarter wavelength transmission line (TL mm), configured to couple the drain of the first amplifier and an output terminal of the first amplifier; and - a fifth quarter wavelength transmission line (TL m), configured to couple the output terminal of the first amplifier and ground by connecting in series with a second capacitor (C 3), wherein the second even order harmonic components are shorted to ground through a signal path via the first quarter wavelength transmission line (TL d0), the fourth quarter wavelength transmission line (TL mm), the fifth quarter wavelength transmission line (TL m), and the second capacitor (C 3). a first transmission device, comprising: - a first quarter wave length transmission line (TL d0), configured to couple a drain of the first amplifier and a drain of the second amplifier, and feed first even order harmonic components generated at the drain of the first amplifier to the drain of the second amplifier; - a second quarter wavelength transmission line (TL mp), configured to couple the drain of the second amplifier and an output terminal of the second amplifier; and - a third quarter wavelength transmission line (TL p), configured to couple the output terminal of the second amplifier and ground by connecting in series with a first capacitor (C 4), - a first quarter wave length transmission line (TL d0), configured to couple a drain of the first amplifier and a drain of the second amplifier, and feed first even order harmonic components generated at the drain of the first amplifier to the drain of the second amplifier; - a second quarter wavelength transmission line (TL mp), configured to couple the drain of the second amplifier and an output terminal of the second amplifier; and - a third quarter wavelength transmission line (TL p), configured to couple the output terminal of the second amplifier and ground by connecting in series with a first capacitor (C 4), wherein the first even order harmonic components are shorted to ground through a signal path via the first quarter wavelength transmission line (TL d0), the second quarter wavelength transmission line (TL mp), the third quarter wavelength transmission line (TL p), and the first capacitor (C 4); and a second transmission device, comprising: - the first quarter wavelength transmission line (TL d0), wherein the first quarter wavelength transmission line (TL d0) is further configured to feed second even order harmonic components generated at the drain of the second amplifier to the drain of the first amplifier; - a fourth quarter wavelength transmission line (TL mm), configured to couple the drain of the first amplifier and an output terminal of the first amplifier; and - a fifth quarter wavelength transmission line (TL m), configured to couple the output terminal of the first amplifier and ground by connecting in series with a second capacitor (C 3), - the first quarter wavelength transmission line (TL d0), wherein the first quarter wavelength transmission line (TL d0) is further configured to feed second even order harmonic components generated at the drain of the second amplifier to the drain of the first amplifier; - a fourth quarter wavelength transmission line (TL mm), configured to couple the drain of the first amplifier and an output terminal of the first amplifier; and - a fifth quarter wavelength transmission line (TL m), configured to couple the output terminal of the first amplifier and ground by connecting in series with a second capacitor (C 3), wherein the second even order harmonic components are shorted to ground through a signal path via the first quarter wavelength transmission line (TL d0), the fourth quarter wavelength transmission line (TL mm), the fifth quarter wavelength transmission line (TL m), and the second capacitor (C 3).