PURPOSE: To easily connect a plurality of beams extending at least to two directions with a column through a simple joint metal fitting.

CONSTITUTION: A plurality of vertical ribs 3a, 3a protruding along a beam 2 respectively, at joint metal fitting 3 of a column and a beam, are provided. A plurality of bolt holes 8 in which joint bolts 6 can be inserted in order to join the beam 2 to the vertical rib 3a are provided at the upper and lower positions with respective distances and protruded at the end of the beam 2 along one of the vertical rib 3a. And a joint metal fitting 5 of the beam composed of the web 5a having a plurality of loose holes 11 in which the head of connection bolt 6 can pierce in the corresponding position to the bolt holes 8 of this vertical rib 3a, and a flange 5b having a plurality of bolt holes 12 in which the connection bolt 6 can pierce in the corresponding position to the bolt hole 8 of the vertical rib 3a and protruding from the front end of the web 5a along the other vertical rib 3a, are protrusively provided respectively. The bolt hole 8 of the vertical rib 3a is fastened together with the bolt hole 12 of the flange 5b with the connection bolt 6.