This paper investigates how the activities and participation of people with disabilities influence their social exclusion, focusing on the moderating effect of disability identity. We used surveys to develop a social exclusion scale of people with disabilities. We sent the survey to the gatekeepers who worked at welfare agencies for people with disabilities and sites for independent living, so that the gatekeepers could contact persons with disabilities in order to ask their cooperation on the survey. Through the gatekeepers, we surveyed 840 people with disabilities across the country including Seoul, Daejeon, Gangwon, Gwangju, and Busan. After the exclusion of insincere responses, 810 out of 840 respondents were identified to make up the final sample. The results indicated that the activities and participation of people with disabilities negatively influence four types of social exclusion. Specifically, those who are more active participants experience lower levels of social exclusion as well as its four subsets than other people with disabilities do. Second, the relationship between activities and participation and the total score of social exclusion, exclusion from social rights, exclusion from participation and relationships, and exclusion based on culture and norms was moderated by disability identity. Based on these findings, we suggest changes in policy and practice to lessen the social exclusion of people with disabilities in Korea.