The invention provides a biosynthetic gene cluster of Rubrolone as a tropolone natural product, Streptomyces sp. CGMCC No.11535, a preparation method for preparing Rubrolone compounds 1-4 from the biosynthetic gene cluster and the Streptomyces sp., a medicinal composition taking the Rubrolone compounds as active components, and application of the biosynthetic gene cluster to pharmacy. By adopting all gene and protein information which is relevant to Rubrolone biosynthesis, a biosynthesis mechanism of the Rubrolone as the natural product is known, and materials and knowledge are provided for further genetic modification. Genes provided by the invention and a protein thereof can be used for finding compounds, genes or proteins applicable to medicine, industry or agriculture.