The homeless encounter many barriers to health care and preventive services, while having an increased prevalence of most risk factors for cancer. A group of homeless adults (221) at nine different locations within Los Angeles County were surveyed during the summers of 1998 and 1999. A portion (71%) reported that they had had at least one rectal exam, 42% had a fecal occult blood test, 24% had a skin exam, and 23% had an endoscopy (flexible sigmoidoscopy or colonoscopy), and of the men aged 50+, only 19% had a prostate-specific antigen test in their lifetime. For women aged 40+, 55% had received a Pap smear, and 53% had a breast exam, but only 32% had a mammogram within the prior year. Among the sampled homeless population, 77% believed in the benefits of cancer screening, 79% were not fatalistic about cancer, 63% believed that early detection was efficacious, and 83% did not think it would be difficult to get screened. The majority of this population demonstrated accurate knowledge of cancer screening guidelines with the exception of endoscopy. Cancer screening rates of those surveyed were lower than the rates in California for endoscopy, prostate-specific antigen, mammography, and Pap smears. Given the lower cancer screening rates compounded by higher cancer risk factors, homeless populations need increased access to cancer screening tests, as well as education on the availability of free services. Additionally, facilities for the homeless and their staff should reinforce the purposes of cancer screening, provide more screening services, and implement institutional efforts, such as providing nutritious meals and sun protection products, to reduce high-risk behaviors and increase further access to cancer screening tests.