Abstract: Using the Plant Canopy Analyzer（PCA），authors nondestructively measured the leaf area index （LAIPCA）and diffuse noneinterceptance（DIFN） of 8 isolated Vitex negundo L. canopies. The light transmittance（τ）was measuredusing LI200SA sensor and LAIharvest of the 8 canopies was measured using harvesting method（total defoliation）.Then the correlation and deviation of LAIPCA and LAIharvest，also DIFN and τ， were compared. The results showed that （1）LAIPCA measured by LAI2200 PCA was closely related to LAIharvest obtained with the harvesting method，passed through the significant test at 0.01 reliability. LAIPCA measured by LAI2200 PCA was 2.57% higher than that obtained  with the harvesting method （total defoliation），which indicated that LAI2200 had small deviation when used to measure LAI of isolated forest canopy.（2）DIFN measured by LAI2200 PCA closely related to the light transmittance（τ）measured by LI200SA sensor（P<0.01）. It indicated that LAI2200 PCA can be used to measure vitex shrub isolated canopy LAI and light transmittance replacing total defoliation method. The paper demonstrated isolated forest canopy analyzing method，which widely presents in the practice of forestry production.

Key words: Isolated canopy, Canopy analyzing, LAI2200, DIFN, Transmittance