Abstract: The water-balance of typical Phyllostachys edulis forests(Ph. edulis and Cunninghamia lanceolata mixed forest, Ph. edulis pure forest and Ph. edulis and broad-leaved tree mixed forest)were studied in comparison with C. lanceolata forest and evergreen broadleaved forest in the North of Fujian province. The result showed that main income of the stand water was precipitation and the expenditure was evapotranspiration, system moisture change and the amount of runoff. The evaporation was the maximum item of water output, accounting for 97.69% to 99.12% of the precipitation and the runoff was minimum item, accounting for 0.52% to 1.11% of precipitation. The moso bamboo forest was in the status of water-balance because their actual expenditure of all forest stands was less than the actual input water. However, there was seasonal water shortage for those forest types. The evapotranspiration exceeded the amount of rainfall in Febr to Mar and Aug to Oct. It was important to replenished water for the growth of bamboo forest. The community structure had important effect on water balance. The correlation coefficient between the biomass and the expenditure was different in different months. The correlation between the biomass and the expenditure was stronger when the rainfall was less. There was a close relationship between the species numbers and the expenditure items. The evapotranspiration coefficient was higher and the water variation ratio was lower when the number of species was more. Ph. edulis and broad-leaved tree mixed forest was a good business model because it could maintain species diversity, replenishment the soil moisture quickly and had greater productivity.