Voice/text/image commercial information generating method and device during a communication is on wait. The method includes the steps of: checking a telephone call, connecting with a commercial information ringback tone generating system/device at an originating or a receiving communication system when the call is detected, beginning to transmit a commercial information in forms of voice/text/image instead of the original ringback tone or a guide message to an originating telephone from the commercial information ringback tone generating system during a communication wait, requesting a connection to a receiving telephone from the commercial information ringback tone generating system after an A-timeout lapses, continuously transmitting the commercial information to the originating telephone, checking whether the receiving telephone accepts the connection request, stopping the providing of the commercial information ringback tone if the telephone connection is made, connecting a communication line between the originating and the receiving telephones, checking whether the communication is finished, and disconnecting the communication line if the communication finishes.