A nitrogen oxide removal equipment for removing nitrogen oxide contained in gas, comprising: a nitrogen oxide absorption means (94, 100) provided with an absorption unit for removing nitrogen oxide contained in said gas by passing said gas through a solid absorbent layer, said absorption unit comprising: an absorbent storage part surrounded by a boundary wall of a storage part, a bottom panel of a storage part, and an upper portion of an outlet side, and provided with said solid absorbent layers therein; and a low-profile unit body provided with a gas rectification part for rectifying gas passing through said solid absorbent layers, and said unit body comprising: an intake side surface; an outlet side surface disposed opposite to said intake side surface and provided with said upper portion of said outlet side and a lower portion of an outlet side; said storage part boundary wall disposed between said intake side surface and said outlet side surface; said bottom panel of said storage part disposed horizontally from a lower end of said boundary wall of said storage part to said upper portion of said outlet side; a bottom of said rectification part being disposed below a boundary of an outlet side, said boundary being between said upper portion of said outlet side and said lower portion of said outlet side; a bottom panel of said intake side extending from said intake side surface to said bottom of said rectification part; and a bottom panel of said outlet side extending from said boundary of said outlet side to said bottom of said rectification part, wherein the ratio of A: B is in a range of 1: 1 to 1: 10, where A represents a distance from a boundary between said bottom of said rectification part and said bottom panel of said outlet side to said bottom panel of said storage part while B represents a distance from said boundary to said outlet side surface. a nitrogen oxide absorption means (94, 100) provided with an absorption unit for removing nitrogen oxide contained in said gas by passing said gas through a solid absorbent layer, said absorption unit comprising: an absorbent storage part surrounded by a boundary wall of a storage part, a bottom panel of a storage part, and an upper portion of an outlet side, and provided with said solid absorbent layers therein; and a low-profile unit body provided with a gas rectification part for rectifying gas passing through said solid absorbent layers, and an absorbent storage part surrounded by a boundary wall of a storage part, a bottom panel of a storage part, and an upper portion of an outlet side, and provided with said solid absorbent layers therein; and a low-profile unit body provided with a gas rectification part for rectifying gas passing through said solid absorbent layers, and said unit body comprising: an intake side surface; an outlet side surface disposed opposite to said intake side surface and provided with said upper portion of said outlet side and a lower portion of an outlet side; said storage part boundary wall disposed between said intake side surface and said outlet side surface; said bottom panel of said storage part disposed horizontally from a lower end of said boundary wall of said storage part to said upper portion of said outlet side; a bottom of said rectification part being disposed below a boundary of an outlet side, said boundary being between said upper portion of said outlet side and said lower portion of said outlet side; a bottom panel of said intake side extending from said intake side surface to said bottom of said rectification part; and a bottom panel of said outlet side extending from said boundary of said outlet side to said bottom of said rectification part, an intake side surface; an outlet side surface disposed opposite to said intake side surface and provided with said upper portion of said outlet side and a lower portion of an outlet side; said storage part boundary wall disposed between said intake side surface and said outlet side surface; said bottom panel of said storage part disposed horizontally from a lower end of said boundary wall of said storage part to said upper portion of said outlet side; a bottom of said rectification part being disposed below a boundary of an outlet side, said boundary being between said upper portion of said outlet side and said lower portion of said outlet side; a bottom panel of said intake side extending from said intake side surface to said bottom of said rectification part; and a bottom panel of said outlet side extending from said boundary of said outlet side to said bottom of said rectification part,