Scientists have been searching an effective tool for solving the safety issue of GM (genetically modified) plants for many years. The group led by Chinese American scientist Yi Li, a professor at University of Connecticut, made a great breakthrough in this field after 6 years' intensive research: his group published the 'Gene-deletor' technology in 2007. The technology was developed from two recombination systems Cre/Loxp and FLP/FRT, and FLP/Cre was driven by Organ/Tissue-specific promoter, all transgenic foreign genes will be thoroughly removed from pollen, fruit and seed after they have accomplished function. It could effectively prevent GM gene flow into non-biotech plants or weeds, and may help alleviate public concerns on ecological risks and food safety caused by GM plants. Here the concept, principle of 'gene-deletor' technology were introduced and its applications in genetic engineering research were discussed.