Light use efficiency of rice leaves were analyzed using chlorophyll fluorescence spectra in the present research. First of all, photosynthetic rate (net CO2 assimilation rate) of individual leaves and incident photosynthetic active radiation were accessed, and photosynthetic light use efficiency was calculated with them. Meanwhile, laser induced chlorophyll fluorescence emission spectra of leaves of rice under different light use efficiency were measured using a compact fiber-optic fluorosensor with a solid-state laser at 473nm as exciting source and an integrated fiber optic spectrometer at ambient temperature. Then, specific fluorescence spectral bands of leaves were selected to analyze light use efficiency. Significant relations of light use efficiency with F685， F732 and the fluorescence ratio F685/F732 were found, thus indicating functional relations among these parameters. The results show that the precision of the function based on the fluorescence ratio F685/F732 is higher. The assimilation process of CO2 is affected by stomatal conductance and the temperature of leaves is a signature of stomatal conductance. An inverse relation was also found between light use efficiency and temperature of leaves. So measured fluorescence spectra were fitted with a linear combination of regression function corrected by the temperature of leaves to predict light use efficiency，R2=0.885.