The invention discloses a novel platinum (II) coordination compound of an oxidation iso-aporphine alkaloid (namely mono-chloride-dimethylsulfoxide-6-hydroxide radical oxidation iso-aporphine platinum (II)) and a synthesizing method and application of the mono-chloride-dimethylsulfoxide-6-hydroxide radical oxidation iso-aporphine platinum (II). According to the coordination compound, 6-hydroxide radical oxidation iso-aporphine and dichloro-dimethylsulfoxide platinum (II) which are equal in amount of substance are weighed and dissolved in a polar solvent, and a target product is obtained after a heating reaction or a reflux reaction; in detail, a solution method can be used for synthesizing, and meanwhile a solvothermal method can be used for synthesizing. Proliferation inhibition, on HepG2, SK-OV-3, SK-OV-3/DDP, BEL-7404, T-24 and other human tumor cell stains, of the coordination compound is investigated, the result shows that the novel platinum coordination compound has obvious anti-tumor activity in vitro and good potential medicinal value and is expected to be used for preparation of kinds of anti-tumor drugs. The chemical structural formula of the coordination compound is as follows (please find the formula in the specification).