In a synthesis of a borazine compound by a reaction of an alkali boron hydride represented by ABH4 (A represents lithium atom, sodium atom or potassium atom) and an amine salt represented by (RNH3)nX (R represents a hydrogen atom or an alkyl group, X represents a sulfate group or a halogen atom, and n is 1 or 2), or b) diborane (B2H6) and an amine represented by RNH2 (R represents a hydrogen atom or an alkyl group), a water content of raw material is controlled below a prescribed value; mixed solvents containing solvents each having a prescribed boiling point are used as a solvent for reaction; or a raw material is gradually fed to a reactor in a reaction. Or, a borazine compound is subjected to distillation purification treatment and filtration treatment. By such a method, a high purity of borazine compound can be produced safely and in a high yield.