Rice is the staple food for more than half of the world population. With the boom in transgenic rice varieties all over the world, a fear of consuming transgenic rice food has been triggered. Although rice is mainly consumed as milled rice, more and more processed rice products such as fermented rice wine, infant cereals, congee, and crackers have become available in food markets in many countries. Food manufacturing entails a number of complex processing steps including physically shearing, high temperature, high pressure, and fermentation. Each food processing step contributes to an unique environment in which DNA undergoes deterioration. This review discusses research on the detection of DNA degradation in GM rice food and the analytic techniques. The data show that both recombinant DNA and endogenous genes in GM rice experience fragmentation during rice food processing. Except for the food processing conditions, DNA extraction, which contains a number of complex chemical and physical steps, is also focused on in this chapter for the DNA damage detection in GM rice food. For the analytic techniques, PCR has been widely used in the detection of GM rice food, owing to its high efficiency and specificity, ease of use, and adaptivities for both qualitative and quantitative detections.