The accurate estimation of foliar chlorophyll concentration contributes to our need for further understanding of forest ecosystem. Two approaches, namely, indices and partial lease squares regression, were used to retrieve foliar chlorophyll concentration, both of which are based on the spectra and chemical variables of main tree species in Qianyanzhou forest. Common hyperspectral indices were used to set up the regression model, and a new index, Chlorophyll Absorption Area Index (CAAI), was created. The results show that the indices TCARI and CAAI have stronger ability for predicting chlorophyll concentration, and the predicted model constructed by the PLS method can be used to explain the capability of these indices.