Nutrient limitation (mostly nitrogen or phosphorus) is thought be a driving force in ecosystem development. It was hypothesized that the N:P ratio of the vegetation directly reflects the nature of nutrient limitation. At vegetation level, N:P ratios <14 and >16 often correspond to N- and P-limited biomass production. The study on nitrogen (N) and phosphorus (P) contents of plants thus may greatly increase our limited knowledge of the nature of nutrient limitation and also provide guidance for ecological restoration. This paper investigated N and P contents of 44 wetland plants from the Lake Erhai basin. The results showed that the mean contents of N and P were 15.7 mg/g and 3.3 mg/g dry weight, and ranged from 6.4 to 34.3 mg/g for N and 1.4 to 6.5 mg/g for P, respectively, and they were markedly higher than those from other regions. The N ∶ P ratio ranged from 2.2 to 9.5, indicating that N was the limiting factor in the Lake Erhai basin. There was a significant difference in N and P contents between above- and belowground parts in plants. The mean N content (16.7 mg/g) and P content (3.6 mg/g) of aboveground part were significantly higher than those (N content of 9.8 mg/g and P content of 3.1 mg/g) of belowground part. There was a significant difference in N and P contents among functional groups. Submerged species exhibited significantly higher N contents (17.7 mg/g) than the emergent species (12.1 mg/g) and free-floating/floating-leaved species (13.4 mg/g), while mud-flat species had significantly higher P contents (3.6 mg/g) than submerged species (2.6mg/g). Overall, the biomass, and N and P contents of above-ground tissue respectively accounted for 72%, 82% and 75% of those in the whole plant, which suggested that harvesting of above-ground tissue could effectively remove N and P from wetland ecosystem.