PurposeOnline health communities (OHCs) are attracting more and more healthy consumers, including patients, their families, caregivers and the general public. This paper aims to explore the themes and characteristics of patient-generated content (PGC) in Chinese OHCs.Design/methodology/approachBaidu Tieba for hypertension was selected as the research site. Online ethnography (netnography) approach was utilized to explore the PGC and health communication in the online hypertension community. The final database included 300 randomly sampled threads and their 3,187 reply posts and was further analyzed from three perspectives: health information needs, attitudes and psychological reactions to hypertension and social support exchange.FindingsThe members' health information needs were mainly concentrated on five aspects: causes, symptoms, measuring instrument, tests and diagnosis and treatment. Their attitudes and psychological reactions to hypertension varied with the context, for example, disease stage, health condition. Within the health communication, three types of social support – information support, emotional support and network support – were generated, transmitted and exchanged among members.Practical implicationsOHCs are able to serve as important source of health information and tool for health education. The implications and suggestions for health promotion of individuals, health information services optimization of OHCs and national health strategy plans were also discussed.Originality/valueThis is the first netnography study in information field on Chinese online hypertension community. This study provides a new perspective to explore the needs, attitudes and social support behaviors of Chinese hypertension population and also enables the Chinese experience of using OHCs to reduce health disparities to come to the world.