The invention relates to a door/window glass mounting and fixing structure for a building door/window. The door/window glass mounting and fixing structure comprises a door/window sectional-bar outer frame, wherein door/window glass is fixedly mounted on the inner end face of the sectional-bar outer frame separately through press lines and transfer materials at two sides, the indoor side of the sectional-bar outer frame is connected with a synthetic-resin sectional bar side, and a press line, of which the upper end part transversely presses the indoor side of the door/window glass, is connected onto the synthetic-resin sectional bar side; a transfer connecting material is arranged on the sectional-bar outer frame, the outdoor side of the transfer connecting material is connected with a transfer material, of which the upper end part presses the outdoor side of the door/window glass; the transfer connecting material is of a lumpy sectional bar, the door/window glass made of hollow glass is placed on the upper end face of the transfer connecting material through a glass mat, and the hollow glass is embedded in a mounting groove, which is formed by the outdoor-side transfer material and the indoor-side press line, above the sectional-bar outer frame. The door/window glass mounting and fixing structure has the characteristics that the structure is simple, the use and mounting are convenient, the coefficient of safety of use is increased, the visible plane of the indoor side can be enlarged, the safety and aesthetic property are improved, and the like.