Nitrite is one of the most important additives in meat products. In most countries the use of the additive is limited and either the ingoing or the residual amounts are regulated by laws. N-nitrosamines are formed by amines or amino acids with nitrite in meat. Investigations on the occurrence of N-nitrosamines in meat products have been carried out in many countries around the world. In this paper, mechanism of N-nitrosamine formation and its corresponding influence factors in meat products were reviewed. The contents of N-nitrosamines in meat and analytical techniques for the compounds were also described.