For assessing impacts of Bt rice on the non-target insects, the population parameters of the white-backed planthopper, Sogatella furcifera (Horvath) fed on transgenic cry1Ab rice varieties KMD1 and KMD2 and their parent rice variety XS11 were assayed in the laboratory. The results showed that the innate capacity for increase of S. furcifera on KMD2 was lower than that on XS11 due to the significant reduction of oviposition duration (7.6 d on KMD2 and 12.7 d on XS11, respectively) and the number of eggs laid per female (95.0 on KMD2 and 167.5 on XS11, respectively). The chemical analysis indicated that this might be resulted from the significant difference of contents of total free amino acids, particularly two free amino acids (Ala and Glu) between KMD2 and XS11. But the effect of KMD1 was not the same as that of KMD2 except that there was also a significant reduction of oviposition duration (8.6 d on KMD1). The results suggested that feeding on different rice varieties might have different effects on population development of S. furcifera.