In order to investigate the distribution of precipitation and nitrogen, phosphorus characteristics by canopy interception of Pinus massoniana plantations, the rainfall, throughfall, stemflow and their nitrate (NO₃^-), ammonium (NH₄⁺) and total phosphorus (TP) concentrations were measured in 18 and 32 years old Pinus massoniana plantations at Laifu Town of Yibin City. The results showed that, according to the variations of monthly precipitation, the rain and dry seasons could be defined as from July to November and from January to April, respectively. Canopy interception and nitrogen, phosphorus concentrations were influenced by the rainfall class. Rainfall, interception of throughfall and stemflow were positively correlated with the rainfall class, and the interception in the dry season was less than in the rain season. The monthly average concentrations of TP, NO₃^--N, NH₄⁺-N in the dry season were significantly higher than in the rain season, and there were significant differences between months, whereas there were no significant differences in canopy interception of TN and TP concentrations between the two plantations. The result indicated that there were significant negative correlations between nitrogen and phosphorus concentrations with rainfall, throughfall and stemflow, and the nitrogen and phosphorus concentrations declined significantly with increasing the rainfall.