The platinum group metals (abbreviated as the PGMs; alternatively, the platinoids, platidises, platinum group, platinum metals or platinum group elements (PGEs)) is a term used sometimes to collectively refer to six metallic elements clustered together in the periodic table. These elements are all transition metals, lying in the d-block (groups 8, 9, and 10, periods 5 and 6).

The six platinum group metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum. They have similar physical and chemical properties, and tend to occur together in the same mineral deposits. However they can be further subdivided into the iridium-group platinum group elements (IPGEs: Os, Ir, Ru) and the palladium-group platinum group elements (PPGEs: Rh, Pt, Pd) based on their behaviour in geological systems.

Naturally occurring platinum and platinum-rich alloys have been known by pre-Columbian Americans for many years. Though the metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between Darién (Panama) and Mexico ("up until now impossible to melt by any of the Spanish arts").