Abstract: A perch of the bird cage comprises a perching rod, two retaining members, and two fastening nuts. Each of the two retaining members has one end that is fastened to the perching rod and another end that is provided with a predetermined number of male threads and is further provided axially with a cruciform slot, which is engageable with an upright rod, a horizontal rod of the bird cage, or the junction of the upright rod and the horizontal rod. Each of the two fastening nuts is provided with a predetermined number of female threads engageable with the male threads of the retaining members.