Upon the basis at the end of March 2005, we have the 38.91 million cellular phone subscribers over the country and the total diffusion rate of the cellular phone is reached up to 76.1%. At this moment, it can be said the most people use it since the demand is still going on. Turning to the operation company, this is serviced by the SK Telecom, LG Telecom, and KTF, and there are at least 6 manufactures producing it including Samsung, LG, KTF ever, Motorola an d SKY. Most users periodically change the service vendor to the others for buying new model or changing the service vendor. It is understood the customer's action occurred by the differences of the brand cognition. In this study, along with some parameters including the difference of the vendor's difference of satisfaction (mobile telecommunication, product), and the possibility to buy the product again, I am going to find out the relationship between the satisfaction of the provider's service.