Knowledge sharing among students is one of the essential activities in learning. Recently, it is found that besides face-to-face interactions, students also share their knowledge through online channels such as social software tools. This study aims to examine the relationship between social software characteristics and knowledge sharing behavior of students in Malaysian university context. The findings of the questionnaire survey with 307 students in five different universities revealed that informal setting, communication, network and community, and user-generated content characteristics of social software tools could positively influence students' knowledge sharing behavior. © 2013 IEEE.