PROBLEM TO BE SOLVED: To provide a connection metal fitting capable of firmly connecting and fixing columnar members such as arch pipes constituting a greenhouse, and a connection structure using the metal fitting.SOLUTION: A connection metal fitting comprises: a first fastening part 3 which is in a single-folded shape, formed in a single-folded valley part, formed in a cylindrical shape having a line parallel with a line (valley bottom line) along a valley bottom of the valley part as a central axis, and grips a columnar member； two sidewalls 2a,2b which are formed in a single-folded laminated part, and arranged in a facing manner while having an arc-shaped cross section which has a line perpendicular to the valley bottom line as a central axis, and has a second fastening part 4 equipped with first through-holes 5 which can be fastened with a bolt 13 penetrating the two sidewalls 2a,2b.SELECTED DRAWING: Figure 3【課題】ビニルハウスを構成するアーチパイプ等の円柱状部材を強固に連結して固定することが可能な連結金具およびこれを用いた連結構造の提供。【解決手段】２つ折り形状であり、２つ折りの谷部に形成され、谷部の谷底に沿う線（谷底線）に対して平行な線を中心軸とする円筒状に形成されて円柱状部材を挟み込む第１締着部３と、２つ折りの重なり部に形成され、谷底線に対して垂直な線を中心軸とする円弧状断面を有して向かい合わせに配置された２つの側壁２ａ，２ｂを備えるとともに、当該２つの側壁２ａ，２ｂを貫通してボルト１３により締結可能な第１貫通孔５を備える第２締着部４とを有する。【選択図】図３
