Abstract: Objective To explore the diagnostic value of angiography in small kidney patients. Methods Angiographies were performed in 32 patients with small kidney of unknown etiology or with suspected renal arterial stenosis (RAS). Results Twelve cases of renal atrophy due to RAS were diagnosed by angiography, which demonstrated renal artery stenoses or occlusions. Angiography of 17 patients with nephrogenic renal atrophy displayed homogeneous shrinkage of the renal arteries except in the ostium. In 3 patients with renal hypoplasia, angiography showed narrowed renal arteries and tiny renal arterial branches. Conclusion Renal artery angiography is of important values in the differential diagnosis between renal atrophy due to RAS, nephrogenic renal atrophy and non-renovascular renal atrophy, and renal hypoplasia.