Cyanobacterial blooms and their associated toxins pose a great threat to human beings. The situation is even worse for those whose drinking water source is a cyanotoxin-polluted water body. Therefore, efficient and safe treatments urgently need to be developed. The present study verified the application of vitamin C on the inhibition of toxic Microcystis aeruginosa. Our results showed that vitamin C drove the Fenton reaction and significantly sterilized cultures of M. aeruginosa. The algicidal activity of vitamin C was dependent on its involvement in iron (Fe) metabolism. Vitamin C enhanced iron absorption leading to high ferrous ion levels. The ferrous ion increased production of reactive oxygen species (ROS) by Fenton reaction, which play a crucial role in the killing process. Interestingly, vitamin C also dramatically decreased the release of microcystins. This study highlights the possible benefits of using a vitamin C-induced Fenton reaction to remove M. aeruginosa and microcystins from drinking water sources. (C) 2016 Elsevier B.V. All rights reserved.