The purpose of this study was to describe characteristics of cancer patients who were attending Internet cancer support groups and to provide direction for future research. A total of 204 cancer patients were recruited through Internet cancer support groups by posting the study announcement on the Web sites of such groups. The participants were asked to fill out Internet survey questionnaires on sociodemographic characteristics and health/disease status. The data were analyzed using descriptive and inferential statistics, including t tests, analysis of variance, and Chi-square tests. Findings indicate that cancer patients recruited through Internet cancer support groups tended to be middle-aged, well-educated, female, and middle class. The findings also indicate that there were significant differences in some characteristics according to gender and ethnicity. Based on the findings, some implications are suggested for future research using and developing Internet cancer support groups.