Soluble reactive phosphorus (SRP) concentrations in wetland surface waters were measured during laboratory incubations in the presence of wetland soils and Typha leaf litter. Aerated water columns above intact soil cores increased in SRP concentration (up to 73 µg L⁻¹) over 28 days, whereas the water column in cores containing soil and a Typha litter layer showed no concentration increase (remained < 5 µg SRP L⁻¹). In the absence of soil, phosphorus (P) uptake by leaf litter and associated microbial biomass occurred rapidly under oxic conditions (max. 24-hr. uptake, 524 ± 90 µg P g⁻¹ dry litter d⁻¹), but uptake was slower and less complete under hypoxic conditions. At the highest tested initial P concentration of 1 mg L⁻¹, P uptake by litter under hypoxic conditions (< 0.5 mg O₂ L⁻¹) was 41% of the oxic rate, or 216 ± 42 µg P g⁻¹ dry litter d⁻¹. Differences between hypoxic and oxic P uptake rates, however, were not observed at initial SRP concentrations of 100 µg L⁻¹ or less. Our results suggest that leaf litter may be important to mitigating soil P release.