Background/Aim: Nephropathy after ingestion of Chinese herbs is known as a rapidly progressive form of interstitial renal fibrosis after a slimming regimen containing aristolochic acid that was identified first in Belgium. Intake of traditional Chinese herbal medicines is very popular in Taiwan. So we looked for similar cases in our hospital. Methods: From 1994 to 1998, we observed 20 Taiwanese patients who underwent renal biopsy for rapidly progressive renal failure of unknown origin. The medical history of these patients gave no clue to the origin of renal impairment, except for the administration of Chinese herbs before the development of renal failure in all cases. Results: Although these patients took herbal medications from various sources for different purposes, their renal biopsy specimens showed strikingly similar histological patterns: extensive paucicellular interstitial fibrosis and tubular atrophy, but the glomeruli were apparently intact. They also had similar clinical features, such as a nearly normal blood pressure, obvious anemia, insignificant edema, low-grade proteinuria, and glucosuria. The renal function declined rapidly in most cases; 15 patients underwent dialysis within 3 months of renal biopsy, and 7 patients received emergency dialysis when they first came to our hospital. On clinical and morphological grounds, the nephropathy in our patients appears similar to Chinese herb nephropathy. Conclusions: Because of the diversity of the herbal regimens used, in addition to aristolochic acid, other unidentified phytotoxins may also play a role in this particular disease entity. There is a strong relation between rapidly progressive interstitial renal fibrosis and the consumption of Chinese herbs.