The invention discloses an epoxy molding compound, and a preparation method and application thereof. The epoxy molding compound comprises purified epoxy resin, a curing agent, a curing accelerator, an inorganic filling material, a reflection conditioning agent and a fire retardant. The preparation method comprises the following steps: preparing the purified epoxy resin at first and then mixing all the above-mentioned raw materials to obtain a mixture; subjecting the mixture to fusing and mixing; and then subjecting a product of mixing to cooling, crushing and magnetic separation so as to obtain the epoxy molding compound. The epoxy molding compound has the advantages of high thermal conductivity, high heat resistance, UV resistance and a low thermal expansion coefficient; and the preparation method is convenient and reliable and can realize batch production of the epoxy molding compound.