Abstract: Polarized fluorescence spectrophotometry was used to study the molecular orientation in the amorphous regions of wood. This paper systematically measured the angular distributions of the polarized of fluorescence intensity of Pinus massoniana and obtained the relationship curve between the degree of orientation in late and early wood and the number of rings from pith. Also the difference between the degree of orientation in radial surface and that in tangential surface was found. This method has significance in realizing the property of wood, and instructing the practice in production of wood.