Using SPOT VEGETATION data, the extraction method of experience model of LAI (leaf area index), we estimate and dynamic analysis the LAI of the northeast in 2000, 2004 and 2008. The results showed that: the LAI values of the Northeast region from 2000 to 2008 appears gradually increasing trend, the lowest average of 3.10 throughout the region in 2000, the highest in 2008, reaching 4.97. Judging from the different regions, changes in Liaoning province is the largest one which increases 136.40 points between 8 years, while Heilongjiang Province is the lowest, increased at only 21.53%. LAI values of Heilongjiang province are all the highest in 2000, 2004 and 2008 mainly because of the rich forest resources, vegetation coverage are relatively good; while in Liaoning province and Inner Mongolia, vegetation coverage is relatively poor. Therefore, the LAI is relatively low.