A brief introduction of U.S Environmental Protection Agency evaluated pesticides and chemicals for carcinogenic potential, the principles to guide evaluation of human cancer potential and procedure. EPA has been published in september 24th, 2008 to assess the possibility of carcinogenic pesticides and chemicals of the total of 171: B-type (most likely human carcinogen) 27, c-type(possible human carcinogen) 65, may be carcinogenic to humans of 34, there is evidence to suggest that the possibility of cancer (but not sufficient to evaluate the potential carcinogenic to humans) 36, a number of Keywords (high doses may have caused to human cancer, low doses are unlikely to have a carcinogenic to humans) 7 and 2 known/may or may not be human cancer-causing pesticide.