A pneumatic-opening-closing glue filling device comprises a pneumatic valve, a glue inlet valve sleeve, a glue inlet joint, a large nut, a first air inlet joint and a second air inlet joint. The pneumatic valve comprises a valve body, a piston rod, an adjusting seat, a fine-turning screw, a locking nut, an axial sealing ring, a radial sealing ring, a piston sealing ring and a piston rod sealing ring. A cylinder sleeve, a piston hole, a guide hole, an adjusting seat connection screw hole, an air joint connection hole, a glue inlet column fixing plate, a glue inlet column, a glue inlet column hole, a U-shaped opening and a valve body fixing hole are arranged on the valve body. The pneumatic valve and the glue inlet valve sleeve are integrated so that the pneumatic valve and the glue inlet valve sleeve are compact in structure and small in size. The fine-turning structure is arranged at the tail portion of the pneumatic valve so that the stroke of the piston rod can be adjusted, sealing accuracy can be recovered through the fine-turning structure after the head portion of the piston rod is worn, and service life is prolonged.