Abstract: To study the factor of N -nitrosamine formation in the simulated meat processing condition. The influence of the temperature, pH, and substrate concentration were studied on N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine ( NDEA ) formation , and the effect of the pH , substrate concentration on N- nitrosopyrrolidine (NPYR ) formation. Results showed that the mount of NDMA and NDEA increased as the temperature increased, meanwhile, decreased as the pH reduced. When the temperature was higher than 80℃, the mount of NDMA and NDEA increased significantly. Faster reduction occurred when pH ranged from 5.4 to 6.2 than in the 6.2⁷.0. With the pH risen , the mount of NPYR generated by proline (Pro) had little change (p>0.05) , but declined by pyrrolidine (p<0.05) . Compared to DEA·HCl, it was easier for DMA·HCl to form N -nitrosamines by interaction with NaNO 2 , all occurred at low temperature during meat processing. Compared with Pro, PYR was easier to form NPYR at higher temperatures. In all these four reactions, more N- nitrosamines were generated when NaNO 2 was excessive. All these suggested that higher temperature, lower pH, higher NaNO 2 facilitated the formation of N-nitrosamine, therefore all these factors should be well controlled during meat process to minimize the level of N-nitrosamine.