Nature is an important source for anti-cancer therapeutics, and nearly half of the currently marketed cancer drugs are derived from natural products. Most of the therapeutic natural products are derived from terrestrial sources, such as paclitaxel, vincristine, epothilones, doxorubicin, etoposide and camptothecin. However, the oceans have received growing interest as a source for new useful bioactive compounds, and there are currently several drugs derived from marine natural products for the treatment of cancer on the market. The current recommended chemotherapy of acute myeloid leukemia (AML) is founded on cytarabine, a molecule derived from a natural product isolated from a marine sponge. However, in order to increase the efficiency of the chemotherapy used in the treatment of AML, it is necessary to develop more targeted drugs with less pronounced side effects. In this review, we argue that marine natural products have many of the desired properties of such a drug, and that prefractionated extract libraries of marine plants, animals and microorganisms should be a part of the screening efforts for new AML chemotherapeutics.