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The concentrations of the foliar and surface soil nutrients and the variation with species and stand age were studied in Pinus spp. plantations in Zhanggutai area, northeast China. The results showed that the total N, total P and C: N ratio of the soil in P. sylvestris var. mongolica stands were significantly higher in comparison with those in P. tabulaeformis and P. densiflora stands. For P. sylvestris var. mongolica, the foliar P concentration appeared to decrease with age, and the foliar N and K concentrations did not show a consistent change with age. As for the different tree species of the similar age, the foliar N and P concentrations were significantly different (p<0.05), being with P. sylvestris var. mongolica>P. densiflora>P. tabulaeformis. The foliar N: P ratio of P. densiflora significantly was higher than P. sylvestris var. mongolica and P. tabulaeformis, while the foliar K was no obvious difference between the three tree species. There were significant correlation ( p<0.05) between soil total N and P, soil organic matter and total P, foliar N and P, but it did not show significant correlations between soil and foliar nutrient concentrations, which might attribute to the excessive litter raking, overgrazing and low soil moisture in this area. Based on the foliar N: P ratio, we introduced a combination threshold index of N: P ratio with their absolute foliar nutrient concentrations to determine the possible limiting nutrient. According to the critical N: P ratio and their absolute foliar N, P concentrations, the P. sylvestris var. mongolica stands showed a decreased N limitation degree with age, the P. densiflora stands showed unlimited by N and P in the whole, and the P. tabulaeformis stands showed co-limited by N and P. No significant difference in soil nutrient concentrations of the surface soils was found between 45, 29, 20-yr-old Pinus sylvestris var. mongolica plantation stands. [ABSTRACT FROM AUTHOR]