Rafflesia arnoldii is a member of the genus Rafflesia. It is noted for producing the largest individual flower on earth. There are some plants with larger flowering organs, the Titan Arum and Talipot palm, but these are technically clusters of many flowers. It occurs only in the rainforests of Sumatra and Borneo in the Indonesia Archipelago.

Molecular studies in 2007 have resulted in the final taxonomy of Rafflesia arnoldii which has been assigned to the family of Euphorbiaceae (Davis et al. 2007).