As the most important resource-obtaining functional organ of plants, fine roots are an important part affecting terrestrial ecosystems. Quantifying the fine root functional traits of Phyllostachys edulis is critical to our understanding of the physiological response and ecological characteristics for bamboo's life-history strategies. To investigate the variation of fine root traits of Phyllostachys edulis with altitude gradient and the adaptation strategies of fine roots, the contents of carbon (C), nitrogen (N), phosphorus (P), specific root length (SRL), specific root area (SRA) and other traits of Ph.edulis's fine roots were measured in Wuyi Mountain at different altitudes (840 m, 1040 m, 1240 m), and the differences of fine root traits at different altitudes and the allometric relationship between them were analyzed. The results showed that:(1) there were significant differences in the contents of C, N, P and the ecological stoichiometry among different altitudes. The content of C in fine roots was the highest at the altitude of 1040 m, with the increase in altitude, the content of N and P decreased, leading to the increase of the ratio of C:N and C:P. (2) There were significant differences on the structural traits of fine roots among different altitudes. As the altitude increased, the average root diameter (AvgDiam), SRL, SRA of fine roots all showed a downward trend, while the root tissue density (RTD) showed an upward trend. (3) There was a significant allometric relationship between fine root traits. The significant isometric relationships were found between N and P content in fine roots, but they showed a significant allometric relationship between C content. There was a significant isometric relationship between SRL and SRA, but they showed a significantly negative isometric relationship with RTD, and showed a significant allometric relationship with N content. The significantly negative allometric relationships were found between AvgDiam and RTD. There was a significant difference of fine root functional traits among different altitudes, and a significant allometric relationship between them. Our research showed that there was a trade-off between fine root acquisitive traits (such as SRL) and conservative traits (such as RTD). Ph.edulis tended to increase root length for increasing nutrient absorption at altitude of 840 m, and adopted the conservative strategy (such as increasing root tissue density) with increasing altitude. Therefore, Ph.edulis can rationally balance resource allocation among fine root traits to adapt to environmental changes through phenotypic plasticity mechanism.