Prevention is crucial to reducing cancer burden. Awareness of prevention information is critical to engaging the public in prevention activities. We examined 106,610 information requests from the general public to the Cancer Information Service from 2002 to 2006. The percent of requests related to primary prevention decreased in 2003, but otherwise remained stable around 19%. The percent of requests related to secondary prevention decreased over time, from 38% (2003) to 14% (2006). Demographic characteristics were associated with patterns of change across time. Results suggest that efforts are needed to increase public awareness of cancer prevention, particularly among certain populations.