Abstract: An elevated floor board comprising an upper and a lower floor board combined together by means of combining posts on the upper board and cylindrical posts on the lower board fitting with the combining posts, a number of hard gasket rings and soft gasket rings disposed to fit around the combining post to adjust the height of the elevated floor board, one or two separating boards possible to be fixed between the upper and the lower floor board to form two or more cavities between the upper board, the lower board and the separating board(s) for dispose electric or telephone lines to prevent mutual interference.