The invention discloses a steel structure beam-column joint, which comprises a bearing column, a steel beam, a buffer steel block, a protective steel sleeve, a reinforcing bolt, a reinforcing nut, anda bearing supporting plate. The protective steel sleeve sleeves outside the bearing column; the bearing supporting plate is arranged vertically and horizontally on the outer side of the bearing column and is arranged on the lower edge of the protective steel sleeve; the buffer steel block is arranged between the steel beam and the protective steel sleeve, and is placed above the bearing supporting plate; the buffer steel block is internally provided with a groove; and the upper end of the reinforcing bolt is movably arranged in the groove, the lower end of the reinforcing bolt penetrates through the buffer steel block and the bearing supporting plate successively, and the buffer steel block and the bearing supporting plate are fixedly connected by using the reinforcing nut. According to the steel structure beam-column joint, extension treatment of the connection point between the bearing supporting column and the steel beam is realized, at the same time, it is greatly convenient to disassemble and recycle the bearing column and the steel beam, the reinforcing bolt is mounted movably on the inner side of the buffer steel block, thus prefixing of the steel beam and the bearing supporting plate is realized, hole finding time is shortened, and the assembly efficiency is greatly improved.