Thermosetting cyanate resin composition and application of thermosetting cyanate resin composition

The invention relates to a thermosetting cyanate resin composition, which comprises the following components: polyfunctional cyanate, epoxy resin, flame retardant agent and inorganic filler. The thermosetting cyanate resin composition is used for preparing resin substrates, resin compound metal copper foils, prepregs, laminating plates, copper-coating plate laminating plates, printed circuit boards and the like. The thermosetting cyanate resin composition has good heat resistant property, humidity resistant property and flame retardant property and low heat expansion coefficient.