This paper aims to examine the communication phenomena between Japan and Korea during the expansion of the internet and to explorer conditions of virtuous cultural exchange. From the late 1990s to the early 2000s, the rapid penetration of the information highway enhanced the cultural exchange at the level of citizens. Cyberspace opens a new field of conversation and gives an opportunity of cross-border communication without physical constraint. However, the extended opportunity does not automatically guarantee a mutual understanding and a more rational communication. We observe uncountable cases of online flaming and conflict due to extreme chauvinism. For example, the definitive closure of HANworld is a symbol of a demolition of communication by the net right. A case of online forum on the film "Shiri" is a counter example that avoids a nationalistic clash and finally finds a harmonious way of cultural exchange. To explain this successful experience, we can count on the making of intimate relations as we see in online communities, the existence of key persons who have know-how on the conciliation of conflict online, and the characteristic of the site dealing with popular culture. In conclusion, to ameliorate the condition of cross-border cultural exchange, we propose some measures to the intrusion and the cyber attack of intentional net right in the site. In the broader context, it is necessary to introduce digital literacy and multi-culturalism in education programs. To make a deliberative communication situation between two countries which have adversary historical background, we should try to attenuate the group polarization tendency observed in online for a by being disclosed to the different perspectives concerning critical issues.