The invention discloses a waveform signal source directly injected into a power line. The waveform signal source comprises a control unit circuit, a waveform signal generator circuit, a power amplifier circuit and a power frequency isolation signal injection circuit, wherein the control unit circuit is used for controlling the waveform signal generator circuit to generate a signal waveform, receives the input signal of human-computer interaction and displays control information; the waveform signal generator circuit is used for receiving the control signal of the control unit circuit and generates a signal waveform with certain frequency, phase and amplitude under the control of the control unit circuit; the power amplifier circuit is used for receiving the output signal of the waveform signal generator circuit and carrying out distortionless amplification of the signal; and the powder frequency isolation signal injection circuit is used for injecting the output signal of the power amplifier circuit into the power line. The waveform signal source provided by the invention can conveniently, rapidly and effectively inject signals of different frequencies into a power line channel, reduces cost and an error rate, and improves working efficiency.