Food products except nutritive components may contain potential mutagens and carcinogens. Main reasons for presence of those components in foods are improper technological and thermal process as well as bad storage of foods. A review of papers concerning informations about mutagens and carcinogens naturally existents in plants foods, animals foods, and formed during technological processes. The short description of mutagenesis and carcinogenesis processes is also reviewed. The examples of influence of potential mutagens and carcinogens on the health of people are also showed.