Abstract: The present invention discloses a method and a system for accessing an intelligent network as well as related devices. According to the present invention, user input information is pre-stored in an audio frequency signal generating device and an audio frequency signal demodulation unit is pre-set in an SSP/AIP. The access process comprises: the user terminal receives audio frequency signals carrying the user input information sent by the audio frequency signal generating device, and forwards the signals to the SSP/AIP device via the transmission network; the audio frequency signal demodulation unit in the SSP/AIP device demodulates the audio frequency signals, and sends the demodulated user input information to the SCP of the intelligent network; the SCP controls the user terminal to access the intelligent network according to the user input information. The present invention simplifies the user's operating process for accessing the intelligent service and brings convenience to the user.