African-Americans and Hispanic-Americans are disproportionately affected by cancer, yet underrepresented in cancer clinical trials. Because of this, it is important to understand how attitudes and beliefs about clinical trials vary by ethnicity. A national, random sample of 860 adults was given an online survey about attitudes toward clinical trials. We examined willingness to participate in clinical trials, attitudes toward clinical trials, trust in doctors, attitudes toward alternative and complementary medicine, and preferred information channels. Results indicate that African-American and Hispanic-American participants have more negative attitudes about clinical trials, more distrust toward doctors, more interest in complementary and alternative medicine, and less willingness to participate in clinical trials than white/non-Hispanics, although specific factors affecting willingness to participate vary. The channels people turn to for information on clinical trials also varied by ethnicity. These results help explain the ethnic disparities in cancer clinical trial enrollment by highlighting some potential underlying causes and drawing attention to areas of importance to these groups.