Abstract: Understanding the effect of elevated CO₂ on rice quality of indica (IR24) and japonica (Asominori) will offer some breeding materials under future elevated CO₂ environment. The variety IR24 and Asominori were used to research the processing quality, appearance quality, cooking and eating quality responded to Free Air CO₂ Enrichment (FACE, ambient + 200μmol/mol) during 2003 and 2004. Compared to the control, brown rice rate(BRR), milled rice rate (MRR), head rice rate (HRR) of IR24 and Asominori under FACE were reduced -3.14%~-0.21% and -3.14%~-0.33%, respectively; elevated CO₂ had no significant effect on grain length, grain width and grain shape; chalky grain rate of IR24 and Asominori were reduced from 29.63% and 30.81% under FACE to 18.93% and 24.78% under ambient, respectively; elevated CO₂ had no significant effect on amylose content; each index of Rapid Viscosity Analyzer (RVA) responded to elevated CO₂ was not the same, among of them, only peak viscosity was significantly increased in IR24 and Asominori under FACE during two years; crude protein content of IR24 and Asominori were reduced from 11.77% and 10.23% under FACE to 10.97% and 9.91% under ambient, respectively. During two years, among of the detected rice qualities under FACE, only processing quality and eating quality responded to elevated CO₂ were same. The degree of response to FACE in Asominori and IR24 showed that the rice quality of IR24 had greater effect than that of Asominori.