Abstract: Comparative studies were performed on the sensitivity of general versus real-time PCR to analyze Bt63 genetically modified rice. Based on the DNA sequences of rice endogenous gene SPS and structure-specific gene Btc，we selected specific primers and fluorescent probes in attempt to identify Bt63 rice. The results showed good specificity which could be capable of identifying various species. In the sensitivity assay，Bt63 rice was serially diluted according to their mass percentage and then DNA was extracted for PCR amplification. As a result，fluorescent quantative PCR displayed tenfold higher sensitivity than general PCR，whose sensitivity values were 0.1% and 0.01%，respectively. Two types of PCR methods were applied to analyze the food samples，both of which turned out to be good for effective amplification of SPS gene，while Btc gene retained negative. The real-time PCR method avoids the process of gel electrophoresis，with higher security and simplicity，therefore，in our actual daily test，real-time PCR detection of Bt63 genetically modified rice and its products was a fast，sensitive and accurate testing method.

Key words: GMO detection, general PCR, real-time PCR, Bt63 rice