The invention provides novel phenanthridone derivatives and a synthesis method and an antitumor application thereof, and belongs to the technical field of medicine. The provided compounds have been subjected to antitumor activity evaluation to prove that the provided phenanthridone derivatives have an antitumor effect and can be used to prepare antitumor drugs. The phenanthridone derivative (ZYH005) can be used to prevent promyelocytic leukemia and trans-retinoic acid resistant promyelocytic leukemia. The structure of the derivatives is stable, the efficiency is high, the toxicity is low, theeffect concentration is in a nano mole level, and the onset time is short. The shortages of trans-retinoic acid and arsenic trioxide for treating APL (acute promyelocytic leukemia) in clinic can be overcome. The phenanthridone derivative (ZYH005) can inhibit trans-retinoic acid resistant APL in-vivo and in-vitro and solves the drug resistance problem in APL treatment in clinic. The synthesis method does not need the catalysis of transition metals, and thus heavy metal pollution is avoided.