To provide a coloring device for deciduous pine material that can perform a safe coloring operation without a risk of leakage of ammonia.

An annular water reservoir portion 2 is provided around an upper circumferential edge of a liquid tank 1, and a pair of support pillars 5 is provided each at left- and right-hand sides in an opening portion 3 surrounded by this water reservoir portion 2. A receiving beam 6 is provided between these left and right pairs of support pillars 5, and an inner lid 7 and an outer lid 18 are provided over the opening portion 3 so as to be moved between a water-sealed coloring position in which the inner and outer lids 7, 8 dip into the water reservoir portion 12 at lower edge portions thereof for water sealing and a non-coloring position. The inside of the liquid tank 1 is connected to an ammonia water supply element 11, an ammonia water recovery element 12 and a gas deodorizing.exhausting element 14, and an exhaust port 16b connected to the gas deodorizing.exhausting element 14 is disposed in the water reservoir portion 2 in such a manner as to face a air-tight space S between the inner lid 7 and the outer lid 8.