Abstract: To explore the ecological stoichiometric characteristics of C, N and P in leaves of Fraxinus mandshurica from different provenances, and to provide scientific basis for the selection and cultivation of excellent sources of Fraxinus mandshurica, four excellent provenances（Dongfanghong, Tangwanghe, Huinan and Maoershan（compare）） of Fraxinus mandshurica from Maoershan Experimental Forest Farm of Northeast Forestry University were selected as research objects. The seasonal dynamics of C, N and P contents of Fraxinus mandshurica from different provenances, and the allometry relationship of C, N and P contents were analyzed. The results showed that the N and P content of Fraxinus mandshurica leaves gradually decreased during the growing season, the C/N and C/P gradually increased. The N/P increased first and then decreased. There were significant differences in the content of N, P, C/N and C/P in leaves of different provenances at the early growth stage and the flourishing stage. The content of C and N/P were not significantly different in the growing season. The C, N and P contents in the leaves of Fraxinus mandshurica from four provenances had a significant allometric growth relationship. The allometric growth constant of Dongfanghong provenance was significantly different from other provenances. It was forming its own nutrient balance and utilization strategy. The N content of Huinan provenances was higher than that of other provenances, and the C/N and N/P were lower than that of other provenances. It had higher nutrient utilization efficiency. During cultivation process, the nitrogen fertilizer should be applied at the early growth stage of Fraxinus mandshurica and phosphate fertilizer should be applied at the flourishing stage to improve the nutrient utilization efficiency and promote its rapid growth.