The invention discloses a testing circuit and a testing method for audible noise of a high-voltage direct current filter capacitor. The testing circuit comprises a direct current voltage loading circuit, a harmonic current loading circuit and a bridging capacitor, wherein the direct current voltage loading circuit is connected in parallel to the harmonic current loading circuit through the bridging capacitor; the bridging capacitor is connected in parallel to the tested high-voltage direct current filter capacitor sample, the tested sample is charged with a direct current voltage and the bridging capacitor is also charged the same direct current voltage; the bridging capacitor is also connected in series with the tested sample in the harmonic current loading circuit, and the harmonic current flowing through the bridging capacitor is numerically the same as that flowing through the tested sample. The direct current voltage loading circuit is connected in parallel to the harmonic current loading circuit through the bridging capacitor, so that the safety of the harmonic current loading circuit is ensured and the harmonic current can be output to the high-voltage direct current filter capacitor. Meanwhile, a rectifying silicon stack and a current limiting resistor in the direct current voltage loading circuit play a role in blocking the harmonic voltage, thus ensuring that a power frequency power supply is not influenced.