The invention discloses a veneer longitudinal glue splicing process and a veneer longitudinal glue splicing machine. The veneer longitudinal glue splicing machine comprises a main frame, a tooth cutting device, a tooth cutting conveying device, a tooth joint conveying device, a plate discharging conveying device, a clamping plate moving device, a gluing device, a tooth joint device, a fixed-lengthcutting device, an optoelectronic switch and a controller. The horizontal spacing distance between the tooth joint device and the tooth cutting device is limited to range from 45 cm to 90 cm, the displacement distance of a veneer after tooth beating and before splicing is reduced, errors are reduced, and the tooth joint precision is improved; a good tooth joint effect can be achieved for a wood plate with the tooth length of 3 cm after tooth combing, consumables of the tooth joint end of the veneer are reduced, and the utilization rate of the veneer is increased; the occupied space of complete equipment is reduced, the weight of the complete equipment is reduced, and the consumable cost and transportation cost of equipment products are reduced; and the application range is wide, and various veneers with different lengths, veneers with different thicknesses and veneers adhered with impurities can be longitudinally spliced by a single glue splicing machine.