OBJECTIVE To observe the sub-chronic toxic effects of the genetically modified rice with double antisense SBE gene. METHODS Based on gender and weight, weanling Wistar rats were randomly sorted into five groups: non-genetically modified rice group (group A), genetically modified rice group (group B), half genetically modified rice group (group C), quarter genetically modified rice group (group D) and AIN-93G normal diet group (group E). Indicators were the followings: body weight, food consumption, blood routine, blood biochemical test, organ weight, bone density and pathological examination of organs. RESULTS At the middle of the experiment, the percentage of monocyte of female group B was less than that of group E (P < 0.05). AST activity of female group B was higher than that of group E (P < 0.05). ALT activity of female group C was higher than that of groups A and E (P < 0.05). At the end of the experiment, AST and ALT activities of female group B were higher than those of group E (P < 0.05). Hematocrit (HCT) and blood urea nitrogen (BUN) level of male group B were less than those of group A (P < 0.05), and monocyte was higher than that of group E (P < 0.05). The brain index of female group B was higher than group A (P < 0.05) and the kidney index of group E were higher than those of groups B, C and D (P < 0.05). There were no significant difference of blood lipids, calcium and bone mineral density among all groups (P > 0.05), and no notable abnormity in the pathological examination of main organs (P > 0.05). CONCLUSIONS There were no enough evidence to confirm the sub-chronic toxicity of genetically modified rice on rats.