The relationship between NPP and phenological changes is of great significance to the study of regional ecosystem processes. In this paper, firstly, NPP was estimated with remote sensing models based on GIMMS NDVI3g dataset, meteorological data and the vegetation map in Northeast China. Then phenology was identified with a dynamic threshold method based on NDVI time series which was reconstruct by polynomial function. Finally, the relationship between NPP and phenology was analyzed. Conclusions can be drawn as follows : 1) During 1982 to 2013, the mean NPP ranged from 100 to 700 gC ·m~(-2) ·a~(-1) in Northeast China. The NPP of the most area of farmland and forestland had an increasing trend(0~50 gC ·m~(-2)·a~(-1)). The NPP of grassland,meadow,and forest-agriculture ecotones showed a decreasing trend(0~100 gC ·m~(-2)·a~(-1)). 2) In the farmland, the start of the growing season was located between DOY 121 and 150, the end of the growing season was located between DOY 271 and 280,and the length of the growing season ranged from 120 to 150 days which had a decreasing trend(1~30 days). In most of forestland,the start of the growing season was located between DOY 100 and 120,the end of the growing season varied greatly with region and mainly ranged from 261 to 290 days,and the length of the growing season showed an increasing trend(1 ~30 days). 3)There was a positive correlation between NPP and the start of the growing season in farmland and grassland,and negatively correlated with the end of the growing season and the length of the growing season, which was mainly due to the influence of man-made. Especially, the vigorous growth period of farmland was mainly from July to September, thus NPP increased in this period The NPP of shrubland was negatively correlated with the start of the growing season, and positively correlated with the length of the growing season. The relationships between NPP and phenological indicators (the start of the growing season, the end of the growing season, the length of the growing season) were different due to their geographical location in deciduous needle-leaf forest and deciduous broad-leaf forest and meadow. For the forestland and meadow, the values of NDVI showed different trends in different areas from June to September, which indicated that NPP was not only related to the growth of vegetation in the vigorous growth period,but also may be related to climate change and other factors in recent years. On the whole, the responses of vegetation NPP to phenology in Northeast China were more complex, showing obvious difference of vegetation types and spatial variability,and the topography, community structure and other factors were still needed to be considered in-depth study.