In Korea, a few companies have adopted Siebel, mySAP CRM packages in 2001,2002 This thesis say that what factors are important to selecting these packages and what level of customer satisfaction on reference sites in Korea. As a result, important factors which was founded through the literature research in selecting Siebel, mySAP CRM packages are Fitness, Customization, Usability , Integration, Price. A survey is conducted to get a customer satisfaction service level of those factors on reference sites in Korea. Eight companies, four Siebel reference sites and four SAP reference sites, participated in survey. That survey composed of two parts. First part measure what level of customer expectation of those factors before using these package and its changes of those factors after using these package. Second part measure relative importance of these factors before using these package and its changes of relative importance of those factors after using these packages. As a result, Siebel users (4 users) in Korea say that the relative importance order of important factors is fitness, usability, integration, customization, price and expectation level of those factors is above normal, but experience level of those factors is normal. MySAP CRM users (4 users) in Korea say that the relative importance order of important factors is fitness, usability- integration, customization, price and expectation level of those factors is below normal, but experience level of those factors is more less than the expectation. In conclusion, fitness is the most important factor of selecting Siebel, mySAP CRM packages, and Sibel, mySAP CRM packages, well known foreign packages, have a low performance on important five factors in Korea.