Monthly precipitation measured by TRMM 3B43V6 was compared with that of rain gauge values from meteorological stations over the Inland River Basins of Northwest China to evaluate the precision of TRMM precipitation products. In general, TRMM performed best for low and medium precipitation (pcp < 100 mm, 0.5 ≤ R2 ≤ 0.941), but was biased upward for the high precipitation (pcp > 300 mm, R2 < 0.3). The agreement between TRMM and gauge precipitation estimates was well at monthly time scales for most of the basins, although the TRMM tends to provide slightly larger than the gauge data (−4.04 < BIAS < 0). The TRMM data displayed patterns of annual precipitation were mostly similar to those based on the rain gauges throughout the basin. This analysis shows that TRMM has potential for detecting precipitation in data-sparse regions.