Chlorophyll concentration is an important index for evaluating water quality.To make the inversion of remote sensing more accurate and more reality

it is significant to build analytic model for simulating water（R（0

-

）

） and by the analytic model to inverse chlorophyll concentration.18 points in Taihu lake were chosen

and at those points

the spectra of the water and water chlorophyll concentration were measured at the same time in June

2004.The simulation model of R（0

-

） was built using Gordon model

and the chlorophyll concentration was inversed using optimization method.The correlation of measured and inversed R（0

-

） is 0.99.When the chlorophyll concentration is higher than 30mg/m

3

the relative error of inversed value is less than 20%.Then

the chlorophyll concentration is inversed by this model for seven measured samples in July

2004.The correlation of measured and inversed R（0

-

） is 0.94.And the relative error of the majority points is less than 60%.