Abstract: In order to assess the effect of food processing on the stability of exogenous genes in transgenic rice, fermented glutinous rice and rice cracker were made by using transgenic rice with Bar and Bt gene as main material. The degradation of exogenous gene (CaMV35S promoter, Ubiquitin promoter, NOS terminator, Bar gene and Bt gene) were detected by using different fragments-size PCR primers. It was found that the stability of genes was different under different processing conditions. The fragments whose length is under 200bp are characteristic of higher GC content (except NOS terminator) and good stability.