This research aims to explain the negative side of ICT-enabled communications. Therefore, the perception of users that social interactions on online social networks (OSN) are threatening is suggested as a new variable called social interaction overload. The paper theorizes that individual, OSN-specific, and OSN-specific communication characteristics manifest the extent to which social interaction overload is perceived and how users response to it in a psychological and behavioral manner. Results of an empirical survey with 246 OSN users validate the assumed effects, so that we identify age, number of friends, and communication content as contribution factors of social interaction overload, which in turn has a direct effect on the two outcome variables satisfaction and continuous usage intention. Moreover, results reveal that social interaction overload has higher effects on OSN users’ satisfaction than perceived usefulness or perceived enjoyment.