To make it easier to discern a conversation carried out in a virtual space.

An on-line conversation control method includes: a conversation group determination step of determining one or more conversation groups (G01 to G03) to which a plurality of user terminals respectively belong; a group conversation data producing step of producing group conversation data representing a conversation carried out by users of the user terminals belonging to each conversation group based on user voice data acquired from the user terminals belonging to the conversation group; a group position coordinates determination step of determining the position coordinates related to each conversation group based on the position coordinates in a virtual space 20, related to the user terminals belonging to the conversation group; and a group data sending step of sending, to each of the user terminals, the group conversation data and the position coordinates related to at least one conversation group other than the conversation group to which the user terminal belongs.