Quintus Caecilius Metellus Pius (ca 130 BCE or 127 BC – 63 BCE) is a pro-Sullan politician and general.

He is named Pius because of his 99 BC petition to return his father from exile and is true to his cognomen for the constancy and inflexibility with which he always fought for his father's rehabilitation and return to Rome.

He is elected Quaestor in 97 BCE, Tribune in 92 and Pontifex Maximus in 81, Praetor in 89 BCE, Consul in 80.

He withdraws from Rome during the civil war between Marius and Sulla, returning afterward with the latter.

As a military figure, he has his first commands in the war in 109-107 BCE, when he accompanies his father Quintus Caecilius Metellus Numidicus in Numidia during the Jugurthine War, where his father takes him as a simple cadet.

He is later revealed to be one of the best subordinates of Sulla, but without any other objective than fighting the demagogy with which Marius threatens Rome, never participating in the atrocious violence that marks such a troubled phase of the history of Rome.

He is also one of the Roman commanders in the Social War of 90 - 89 BCE.

A Propraetor at that time, Pius storms Venusia and kills the general of the Marsi, Quintus Poppaedius Silo.

In 87 BCE, Pius by the order of Senate, tries to make peace with the Samnites.