We select abnormal expression genes from the gene chips which detected the nitrogen ion beam irra-diated rice, and these genes (NBS-LRR, PGPS/D12, Pherophorin-S, aspartic endopeptidase) involve in stress response and cell number regulation. In order to investigate the characters of these genes expression in rice seedlings stage irradiated by the low-energy iron beam, mRNA were purified from seedlings at different growth stages ranging from 72 to 120 h after implantation (HAI) and analyzed by semi-quantitative RT-PCR. The results showed that different implantation doses could regulate expression level of NBS-LRR1, NBS-LRR2, Pherophorin-S precursor, Aspartic endopeptidase and PGPS/D12, providing the target genes for the molecular mechanism of ion beam mutation.Cited