Dihydroartemisinin, an important artemisinin derivative, presents excellent anti-neoplastic potential. This article reviews the latest progress in the anti-cancer activity of dihydroartemisinin and the possible mechanisms including anti-proliferation, cell cycle arrest, apoptosis induction, anti-angiogenesis and anti-metastasis. Iron (II) or heme may be the direct target for dihydroartemisinin. The broad anti-cancer spectrum, the low toxicity to normal cells and the potential of anti-multi-drug resistant cells make it a likely new anti-cancer candidate compound.