The Fraction of Absorbed Photosynthetically Active Radiation（FPAR） has been recognized as one of the important variables in carbon cycle research of terrestrial ecosystem.According to the physical meaning of FPAR

the concept of effective FPAR

which is FPAR absorbed by chlorophyll within the leaf

is introduced in this article.We developed the effective FPAR remote sensing model using simulated data

and analyzed the feasibility of estimating effective FPAR based on chlorophyll content

which was expected to introduce a way to estimate NPP/GPP using effective FPAR.The results showed:（1） the difference between FPAR absorbed by leaf(FPAR

leaf

) and FPAR absorbed by chlorophyll(FPAR

chl

) cannot be neglected.FPAR

chl

is not more than 50% of FPAR

leaf

basically.The correlation between FPAR

chl

and FPAR

leaf

is nonlinear.（2） A strong correlation was found between chlorophyll content and FPAR

leaf

but the correlation between chlorophyll content and FPAR

chl

is much stronger.So FPAR

leaf

and FPAR

chl

can be accurately estimated based on chlorophyll content

and the estimation average errors are 2.90% and 6.6% respectively.（3） the estimation accuracy of FPAR

leaf

and FPAR

chl

models is higher when chlorophyll content is not less than 20μg/cm

2

.For 60 samples that chlorophyll content is not less than 20μg/cm

2

the average errors of estimated FPAR

leaf

and FPAR

chl

are 1.79% and 5.07% respectively.