A glass composite material comprising a polymer chain selected from the group consisting of polysilane, polygermane, polystannane and a copolymer thereof, and a network structure of a metal oxide consisting of a metal atom bonded to the other metal atom through an oxygen atom, wherein the polymer chain is chemically crosslinked with a glass matrix of the network structure of the metal oxide directly or indirectly, and a volume resistivity measured by setting a ratio of a voltage to a film thickness at 10.sup.6 V/cm according to a disc plate electrode method is not more than 3.times.10.sup.6 .OMEGA.cm.