The rapid growth of the Internet has made computer-mediated communication popular and the use of e-negotiation systems (ENS) has attracted great attention from researchers and practitioners. Whilst most studies of ENS have emphasized their importance in decision support, few have provided suggestions regarding how to choose communication channels while negotiating online so as to maximize the intended benefits. To bridge this knowledge gap, this study integrated theories of Task-Technology Fit, social presence and media richness and empirically examined a research model investigating the effects of different types of negotiation task (more/less analyzable) and communication support (text/video) on e-negotiation performance. A laboratory experiment with a 2 × 2 factorial design and 80 participants was conducted. Findings suggested that greater negotiation efficiency, ENS satisfaction, perceived usefulness and process satisfaction, as well as lower cognitive effort, will be generated w...