Objective : The purpose of this study was to investigate the effect of cognitive level of mild cognitive impaired elderly living in the community on participation in activities and social networks as well as leisure and daily life activities. Methods : The elderly people aged 65 years or older living in the community were selected for the mild cognitive impairment with a score of MMSE-K of 15 or more and 23 or less. MoCA-K was applied in order to examine the cognitive abilities of the subjects and K-ACS and LSNS-18 were applied to confirm the activity participation level and social network index. Results : As a result of examining the relationship between cognition and activity participation, various sub-abilities(spatio-temporal abilities, vocabulary abilities, attention, abstract thinking) of cognition had a significant influence on instrumental activities of daily living, leisure activities and social activities. In addition, all of the sub - abilities of cognition showed a significant correlation with sub-elements of social network. Conclusion : Through this study, it was found that the general elements of cognition influenced activity participation and social network of various areas of mild cognitive impaired elderly people. We suggest that measures for enhancing participation and social participation of the elderly with mild cognitive impairment are provided through follow up studies.