To explore the possibility of establishing the rice rhizobium symbiotic nitrogen fixation system,four genes ( LHK1,NSP1,NSP2 and NIN ) of symbiosis signaling in Lotus japonicus were cotransformed into rice. Transgenic rice plants were obtained. After inoculation with rhizobium,there was no significant difference in the root hairs and epidermis infected by rhizobia of the control and the transgenic plants. The number of lateral root and primordia in transgenic plants was significantly increased compared with those in the control after inoculation 14 days. The results of transcriptional analysis using rice cDNA microarray showed that expression of those genes involved in plant defense response and phytohormone signaling was significantly upregulated in the transgenic plants. It is indicated that leguminous symbiotic genes affect rice response to rhizobia.