With the advancement of the internet and digital technology, e-negotiation through electronic media is increasing to overcome spatial and temporal constraints and to improve the speed and outcomes of information access. The purpose of this study is to find ways to proactively and effectively cope with the growing use of electronic media as negotiation tools and to enhance negotiation capabilities in the digital age. This study conducted qualitative and quantitative comparative research on the characteristics of electronic and face-to-face negotiations, the formation of positive relationships by negotiation medium, and the effects of effective negotiation attitudes and strategies on negotiation outcomes. For this purpose, 60 upper-level undergraduate students in business and economics participated in electronic negotiations using email and computer chat and face-to-face negotiations through direct contact. Qualitative analysis including participant observation, video recording, and interviews was conducted in parallel with quantitative analysis through pre- and post-negotiation surveys. The results showed that while forming positive relationships was more difficult in electronic negotiations than in face-to-face negotiations, the impact of positive relationship formation on negotiation outcomes was greater in electronic negotiations than in face-to-face negotiations. Specifically, electronic negotiations made it more difficult than face-to-face negotiations to form positive relationships through expressions of intimacy, self-disclosure, trust, and cooperative attitudes; the degree of unpleasant communication was higher; and satisfaction with negotiation outcomes was lower. In electronic negotiations, higher negotiation outcomes were observed when there was more interaction time and frequency for positive relationship formation, more sentences expressing intimacy, and more statements and positive emoticons expressing trust, friendly atmosphere, and other positive emotions—demonstrating that active communication efforts had a positive effect on negotiation outcomes. In electronic negotiations, position-based negotiation was more prevalent than in face-to-face negotiations. Regarding negotiation strategies, competitive and cooperative strategies were rarely used in electronic negotiations, while tit-for-tat strategies were frequently employed; in face-to-face negotiations, cooperative strategies were used more than in electronic negotiations. In electronic negotiations, the use of cooperative and tit-for-tat strategies decreased compared to pre-negotiation intentions, while in face-to-face negotiations, the use of competitive and random strategies increased compared to pre-negotiation intentions. Notably, an inverted U-shaped relationship was found between competitive strategy and negotiation outcomes in both electronic and face-to-face negotiations, with higher outcomes achieved when competitive strategies were used moderately. Finally, practical implications derived from the comparative study between electronic and face-to-face negotiations were discussed.