Abstract: The effect of different dosage injection of Fe+ and Ti+ into Cunninghamia lanceolata seeds under 50keV energy condition on seed germination and morphological characteristics and growth indexes of the seedlings were observed in the study. The results show that Fe+ and Ti+ injection had a delay effect on seed germination, the germination rate dropped along with the dosage increase of Fe+ and Ti+ ions injected into the seeds. The early stage of seedling root growth was significantly inhibited by ion beam injection. The root length of the seedlings was sharply reduced along with the increment of Fe+ dosage injected, indicating that the root length of C. lanceolata seedlings was highly sensitive to Fe+ ion. There were no significant differences in seedling height among the treatments and the control group, but the mutation rate of seedligns injected with Fe+ ion was higher than that of injected with Ti+ ion. 7 superior seedlings were selected from treatment group with ion beam injection.