The study uses an empirical methodology to analyze the characteristics and influence of Twitter users who form public opinions about China. The paper finds that with respect to individual users, organizations are dominant forces on Twitter that are generating public opinions about China. Interest groups, media, enterprises and non-governmental organizations are the main organizations. Media organizations, particularly commercial media, play a large role in generating public opinions on Twitter about China. Users involved in Chinese-related discussion topics mostly come from the USA, Canada, China, Japan and other countries. In terms of influence, individuals are higher than organizations. Among individual users, media practitioners have a high and active degree of influence. Traditional media hold the highest influence among users from organizations.