PURPOSE: To eliminate or reduce an echo caused in a hybrid circuit of the telephone set with a simple and inexpensive configuration.

CONSTITUTION: An echo processing circuit 10 is provided to an echo reduction device of the telephone set having a hybrid circuit interconnecting a signal line for a transmission signal St, a signal line for a reception signal Sr and a telephone line. The echo processing circuit 10 is made of a delay circuit 11 giving a predetermined delay time, a transfer function control circuit 12 with a predetermined frequency characteristic and a level characteristic and a subtractor circuit 13. The reception signal Sr being the result of superimposition of the transmission signal St and an echo signal Se from the hybrid circuit is fed to the subtractor circuit 13. The transmission signal St is fed to the subtractor circuit 13 via the delay circuit 11 and the transfer function control circuit 12. The reception signal Sr is extracted by allowing the subtractor circuit 13 to eliminate or reduce the echo signal Se.