Pluto is in the Kupier belt.
The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter . The Kuiper belt ( [ ` kaipər ] or [ ` kœy̯pǝr ] ) , sometimes called the Edgeworth -- Kuiper belt , is a circumstellar disc in the Solar System beyond the ( known ) planets , extending from the orbit of Neptune ( at 30 AU ) to approximately 50 AU from the Sun . Pluto . It was the first Kuiper belt object to be discovered . After 1992 , its planethood was questioned following the discovery of several objects of similar size in the Kuiper belt .