There are five known moons of the dwarf planet Pluto. In order of distance from Pluto, they are Charon, Styx, Nix, Kerberos, and Hydra. Charon, the largest, is mutually tidally locked with Pluto, and is massive enough that Pluto and Charon are sometimes considered a binary dwarf planet.

The innermost and largest moon, Charon, was discovered by James Christy on 22 June 1978, nearly half a century after Pluto was discovered. This led to a substantial revision in estimates of Pluto's size, which had previously assumed that the observed mass and reflected light of the system were all attributable to Pluto alone.

Two additional moons were imaged by astronomers of the Pluto Companion Search Team preparing for the New Horizons mission and working with the Hubble Space Telescope on 15 May 2005, which received the provisional designations S/2005 P 1 and S/2005 P 2. The International Astronomical Union officially named these moons Nix (Pluto II, the inner of the two moons, formerly P 2) and Hydra (Pluto III, the outer moon, formerly P 1), on 21 June 2006. Kerberos, announced on 20 July 2011, was discovered while searching for Plutonian rings. The discovery of Styx was announced on 7 July 2012 while looking for potential hazards for New Horizons.

Charon is about half the diameter of Pluto and is massive enough (nearly one eighth of the mass of Pluto) that the system's barycenter lies between them, approximately 960 kilometres (600 mi) above Pluto's surface. Charon and Pluto are also tidally locked, so that they always present the same face toward each other. The IAU General Assembly in August 2006 considered a proposal that Pluto and Charon be reclassified as a double planet, but the proposal was abandoned. Like Pluto, Charon is a perfect sphere to within measurement uncertainty.

Pluto's four small circumbinary moons orbit Pluto at two to four times the distance of Charon, ranging from Styx at 42,700 kilometres (26,500 mi) to Hydra at 64,800 kilometres (40,300 mi) from the barycenter of the system. They have nearly circular prograde orbits in the same orbital plane as Charon.

All are much smaller than Charon. Nix and Hydra, the two larger moons, are roughly 42 and 55 kilometres (26 and 34 mi) on their longest axis respectively, and Styx and Kerberos are 7 and 12 kilometres (4.3 and 7.5 mi) respectively. All four are irregularly shaped.

The Pluto system is highly compact and largely empty: prograde moons could stably orbit Pluto out to 53% of the Hill radius (the gravitational zone of Pluto's influence) of 6 million km, or out to 69% for retrograde moons. However, only the inner 3% of the region where prograde orbits would be stable is occupied by satellites, and the region from Styx to Hydra is packed so tightly that there is little room for further moons with stable orbits within this region. An intense search conducted by New Horizons confirmed that no moons larger than 4.5 kilometres (2.8 mi) in diameter exist out to distances up to 180,000 kilometres (110,000 mi) from Pluto (6% of the stable region for prograde moons), assuming Charon-like albedoes of 0.38 (for smaller distances, this threshold is still smaller).

The orbits of the moons are confirmed to be circular and coplanar, with inclinations differing less than 0.4° and eccentricities less than 0.005.