Purpose - The use of corporate social activities to implement the concept of corporate social responsibility enhances brand equity and attitude, and strengthens economic competitiveness. In areas such as mobile communications, companies take the responsibility of protecting customers and enhance the quality of the mobile communication service, helping to make an effort to obey the regulations of the public trade order and fair trade agreement, enabling a healthy society through communication with elderly living alone or youths without parents, and enhancing marketing strategies. Research design, data, and methodology - To test the hypothesis, a survey was conducted. The surveyed population includes people who use the big three mobile communication services. The survey was conducted from October 4th to October 14th, 2013. A total of 500 survey questionnaires were circulated and 483 were collected; out of these, 32 were excluded due to missing or incomprehensible information. The data was analyzed with SPSS 18.0 via frequency analysis, trust analysis, search factor analysis, relationship analysis, confirmation factor analysis using AMOS 18.0, and structural equation model analysis. Results - Research on corporate social responsibility has been frequently conducted recently. Companies are perceived as social constituents satisfying the social desires of people in addition to customer needs. Further, companies are returning profits to society to satisfy community needs, because there is greater emphasis on the social responsibilities of companies. Companies' social responsibilities should include marketing strategies and the identification of customer needs. This study shows that social service activities influence brand value, which influences customer attitudes; therefore, social service activities indirectly influence customer attitudes. In order to increase customers' purchasing intention, it is essential to improve brand image via social services and provide a distinctive quality of service. Conclusions - This research has used the purposive selection method in the empirical analysis to identify the effect of social services on brand value and customer attitude. Therefore, this study revealed that businesses, whose ultimate objective is to improve customers' purchasing intention, should promote their brand equity through corporate social responsibility activities and offer a distinct service quality. Limitations in the progress of research were found and future indications to overcome these limitations are suggested as follows. First, survey responders had a limited understanding of social responsibilities; therefore, this concept needs to be explained to people first. Second, the research was done on people who live in Daejeon; thus, it is not representative of the entire country. The research has to be repeated with people in other cities. Third, there is a limitation in the study because the purposive selection method was used on Daejeon customers. In the future, a more precise selection of the population is needed. Fourth, Daejeon has unique geographical and size characteristics. Thus, customers in Seoul and other areas may display different characteristics and research on them may reveal different findings. Therefore, again, this study has to be repeated in other areas.