MicroRNAs (miRNAs) play an important role in cancers. A number of miRNA expression-profiling studies have been done to identify the miRNA signatures of cancers from different cellular origin. There is, however, relatively little information on how anticancer agents regulate miRNA expression. Ellagitannin (BJA3121), 1,3-Di-O-galloyl-4,6-(s)-HHDP-b-D-glucopyranose, is a new natural polyphenol compound isolated from Balanophora Japonica MAKINO. Our preliminary results have shown that BJA3121 had antiproliferative effect and modified the expression of different genes in human HepG2 cancer cells. In this study, we further evaluate whether this antineoplastic compound is able to alter miRNA expression in HepG2 cells. We demonstrated for the first time that BJA3121 can regulate the expression of 25 miRNAs, including 17 upregulated and 8 downregulated miRNAs in HepG2 cells. Our results suggested that BJA3121-modifed miRNA expression can mediate, at least in part, the antiproliferative and multigene regulatory action induced by the compound on HepG2 cancer cells. Copyright © 2009 John Wiley & Sons, Ltd.