The invention relates to the field of steel structure buildings, in particular to a connector and a building with the same; the connector comprises a first connection head, a second connection head and fastening nuts; an end of the first connection head is provided with a screw thread, an end of the first connection head is provided with a first joint portion which is provided with a plurality of jaws, gaps are arranged between the adjacent jaws, an end of the second connection head is provided with a second joint portion which is provided with fastening grooves matching with the jaws, and gaps are arranged between the adjacent fastening grooves. The connector has the advantages that the connector is simple in structure and convenient to mount; the two fastening nuts are first screwed to the first connection head and the second connection head, the first connection head is inserted into the second connection head, the jaws are snap-fitted into the fastening grooves by rotation, and the fastening nuts are tightened to finish mounting; the stability of a steel structure on the connector can be improved so that the connection stability of the whole steel structure is improved.