Social networking sites (SNSs) have attracted attention as network services in organizations. We evaluated what kinds of user attributes and enterprise attributes affected the advantages and disadvantages of SNS in enterprises. We developed a set of hypotheses based on our survey of the literature concerning SNS, and administered a survey using a questionnaire at enterprises. We found that respondents in their 20s or 60s, and who belonged to smaller organizations felt there were advantages. However, those in their 20s and who belonged to smaller organizations also felt there were disadvantages. We also found a tendency that those who responded and had larger numbers of acquaintances in their friends list and larger numbers of participants in the community reported feeling more advantages as well as disadvantages.