Cancer is a disease that occurs as a result of uncontrolled proliferation and growth of cells or cell groups under the influence of various environmental and genetic factors. It is one of the most important social health problems worldwide. Cancer, which ranks second in the list of causes of death worldwide, is predicted to take the first place by 2030. Nitrosamines, which we are exposed to from endogenous and exogenous sources such as diet and tobacco smoke, are very dangerous for living things. Nitrosamines have a direct role in the etiology of some types of cancer. Therefore, in terms of public health, nitrosamine exposure must be prevented. Additionally, further studies are needed to investigate its metabolism. In this section, the biochemistry of nitrosamines and their relationship with cancer will be examined using the studies carried out.