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Carbon (C) occluded in phytolith (PhytOC) is a stable form of C;when PhytOC is returned to the soil through litterfall it is stored in the soil and that can be an effective form for long-term C sequestration.However,few estimates on the rate of PhytOC input to the soil are available.We quantified the amount of litterfall,phytolith and PhytOC returned to the soil over a year in a typical Lei bamboo (Phyllostachys praecox) forest in subtropical China.Litterfall from the bamboo forest was collected monthly for a year.The phytolith and PhytOC concentrations in the litter samples were determined to quantify the annual phytolith and PhytOC return to the soil.The monthly litterfall ranged between 14.81 and 131.18 g m-2,and the phytolith concentration in the monthly litterfall samples ranged between 47.21 and 101.68 g kg-1 of litter mass,with the PhytOC concentration in the phytolith ranged between 29.4 and 44.9 g kg-1 of phytolith,which is equivalent to 1.8 to 3.6 g kg-1 of PhytOC concentration in the litterfall (based on litterfall dry mass).The amount of phytolith input to the soil system was 292.21±69.12 (mean±SD) kg ha-1 yr-1,sequestering 41.45±9.32 kg CO2-e ha-1 yr-1 of C in the studied Lei bamboo forest.We conclude that return of C occluded in phytolith to the soil can be a substantial source of stable soil C and finding means to increase PhytOC storage in the soil should be able to play a significant role in mitigating the rapidly increasing atmospheric CO2 concentration.