The purpose of the present invention is to provide an organic silicon compound which has a vinyl group more reactive than those of the conventional organic silicon compounds and can be bonded with another compound.The present organic silicon compound is represented by the following formula (1), wherein R1 is, independently of each other, a vinyl group or an alkyl group having 1 to 4 carbon atoms, R2 is an alkylene group having 3 to 6 carbon atoms, and R3 is, independently of each other, a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and optionally substituted with one or more fluorine atoms.