In this paper, a wireless multimedia service interacting with key input of a phone number is Presented. In the conventional handset, when the key button is pressed, numbers are displayed or the embedded sound is played. Also, the contents are fixed and cannot be changed. In this paper, we propose a wireless multimedia service playing multimedia contents in accordance with the key input of a phone number. The contents can be downloaded from the wireless internet server. To implement this service, file format, fast codec and download structure are proposed. Using the presented structure, this service is being provided by a telecommunication company in Korea. Various applications based on this service are being expected.