A perforated tray without downcomer in accordance with the present invention satisfies following conditions: (a) The hole has a diameter of 10 mm to 25 mm. (b) Two adjacent holes are spaced by a distance of 1.2 d to 3 d, measured between the two centers. (c) The tray thickness is 2 mm to 8 mm. (d) The opening ratio is 10% to 30%. A perforated tray tower without downcomer fitted with two or more such perforated trays without downcomer in accordance with the present invention satisfies following conditions: (g) Perforated trays are spaced by a distance of 0.1 D to 0.5 D (D denotes the tower diameter). (h) The levelness of each perforated tray is 8 mm or less. (i) If a plurality of perforated trays are used at the same stage, the two most closely located holes that respectively belong to adjacent perforated trays are spaced by a distance of 50 mm to 150 mm, measured between the two centers. By using the perforated tray tower without downcomer, an easily polymerizable compound, such as an (meth)acrylic acid, or a liquid containing such an easily polymerizable compound can be distilled in a stable manner over an extended period of time with the formation of polymers being effectively prevented.