The invention relates to an energy-saving spraying box of a veneer dryer. The energy-saving spraying box structurally comprises a spraying box body 3 which is welded in a right trapezoid by a front side plate, a rear side plate, a cover plate and spraying box bottom plates 1. The top end (small end) of the spraying box body 3 is closed, the bottom end (large end) of the spraying box body 3 is an open spraying box air inlet 10, each spraying box bottom plate 1 is provided with a rectangular spraying groove 2 with a slit nozzle 4, and a guide plate 5 is obliquely mounted on the nozzle 4. The energy-saving spraying box has the advantages that the porous structure is substituted by the tilted groove structure, dry airflow can be sprayed obliquely through the guide plates with a certain oblique angle and is perpendicularly sprayed to the surface of a veneer by being synthesized with transverse speed. Thus, a boundary layer on the surface of the veneer can be favorably damaged to accelerate heat transfer and water evaporation, and drying efficiency and energy conservation can be improved. Meanwhile, the dry airflow can be uniformly sprayed from a slit, no interval breakpoints exist in the middle, and the surface of the veneer can be uniformly heated by the dry airflow.