Abstract: To explore the impact of rare earth elements on the growth of forest, seedling of Parashorea chinensis were treated by different concentrations of lanthanum and cerium solution. The effect of La, Ce on seedling height, diameter and biomass were studied. The results showed that the growth of seedlings was the best under the treatment of 32 mg/L Ce. Compared with the CK, the total increment and the monthly growth of seedling height, the total increment and the monthly growth of ground diameter and the total dry weight were significantly increased by 144.6%, 46.9%, 585.7%, 60.0%, 578.9% respectively. The best growth was under the treatment of 64 mg/L La, but the effect was far less than the Ce. The effects of rare earth element Ce on the seedling height, ground diameter and biomass were significant and could be used to cultivate the seedlings of the P.chinensis. The effects of 2 kinds of rare earth elements on the growth promotion of seedlings were lower under higher concentration.