The present invention relates to novel 1,4-disilacyclohexane derivatives and a preparation method thereof. More particularly, the present invention provides a method for preparing 1,4-disilacyclohexane derivatives with a hexagonal ring structure at high yield through double silylation of an organosilane compound and a vinyl silane compound having an unsaturated double bond using quarternary organophosphonium salts as a catalyst. According to the present invention, tris(silyl)ethanes having three silyl groups in one molecule can be prepared at the same time and the catalyst can be recovered after reaction. Thus, the method is economical and enables mass-production of 1,4-disilacydohexane derivatives and tris(silyl)ethanes which are precursors of organic/inorganic hybrid materials.