The development of genetically engineered (GE) rice offers more opportunities to increase rice productivity and to reduce labor/resource inputs. China has invested tremendously in the research and development of transgenic biotechnology and GE crops, including rice. Consequently, a large number of GM rice lines with diverse novel traits has been developed. Many GE rice lines are undergoing biosafety assessment that is key to the safe use of GE rice. Potential environmental impact caused by transgene escape to wild relatives is still a great concern for the commercial release of GE rice. Three platforms are important to assess potential environmental impacts of insect-resistance transgene flow in rice: (1) estimating frequencies of transgene flow from GE to non-GE rice and wild relatives through field experiments and model simulation; (2) examining the expression of transgenes in wild relatives of rice; and (3) estimating the life-cycle fitness of transgenes introgressed to rice wild relatives. Crop-to-crop gene flow is extremely low (>0.1%) at close spacing, while crop-to-wild gene flow varies significantly, up to 3% in our studies. The Bt transgene expresses normally in crop-wild progeny although with considerable variation at different growth stages. Transgenic hybrid progeny derived from crop-wild/weed crosses showed increased fitness under insect pressure, but no significant differences in fitness were detected between transgenic and non-transgenic populations under low insect pressure. The frequency of transgene escape to non-GE rice is low and can be managed by spatial isolation. It is difficult to stop the flow of the insect-resistance transgenes to wild/weedy rice populations that coexist with GE rice. Given the low ambient insect pressure in habitats where wild/weedy rice populations occur, the environmental impact caused by such gene flow might be limited.