Net primary production (NPP) in the Yellow River Basin, China, during 1982-1999 was estimated with the CASA model using satellite data. The yearly NPP (NPPt) tended to increase during 1982-1999 throughout the Yellow River Basin. A large mean annual NPP for each grid cell was indicated in both the upper and lower reaches, and a low value was indicated in the middle reaches. As for climate data, the mean annual temperature in the Yellow River Basin tended to increase and annual precipitation tended to decrease during 1982-1999. When the relationships between NPP and climate data were analyzed, a strong positive correlation was exhibited between NPP and precipitation.