This study was conducted to explain the relationships of the factors affecting consumers' disease information-seeking behaviour on the Internet in Korea. Similar to other countries, Korea is facing an increasing use of Internet as a resource of health information. With the paradigm shifts towards consumer-centred health service, it is expected that more health care consumers will use the Internet actively in the future. A survey was conducted using a self-selected convenience sample. A conceptual model was derived by extending technology acceptance model and tested via structural equation modelling. The overall goodness of fit of the conceptual model was acceptable. Consumers' health consciousness, perceived health risk and Internet health information use efficacy were found to influence consumers' beliefs, attitude and intention of use disease information on the Internet. But Internet health information use efficacy did not significantly influence perceived usefulness. It was also identified that consumers' perceived credibility of the information in the websites was the main determinant in forming of attitude towards disease information on the Internet. Technology acceptance model has been extended and examined successfully in explaining consumers' disease information-seeking behaviour on the Internet. It was found that consumers' cognitive and affective characteristics, determined as initiators in health-related behaviour, also impacted consumers' disease information-seeking behaviour on the Internet. These findings may be used to help nurses to predict and identify the factors affecting individual's use of disease information on the Internet. Based on this knowledge, nurses will be able to develop nursing intervention programmes for the patients' health management.