Titius Quartinus (died 235) was a Roman usurper.

Usurper of the Roman Empire
Reign235, against Maximinus Thrax
PredecessorMaximinus Thrax
SuccessorMaximinus Thrax
Titus Quartinus
Regnal name
Imperator Caesar Titus Quartinus Augustus

After the death of Alexander Severus and the usurpation of Maximinus Thrax, a unit of archers from Osrhoene in Mesopotamia, proclaimed Quartinus, a former provincial governor and friend of emperor Alexander Severus, purportedly against his own will. Those archers were led by Macedo and claimed to want revenge for Alexander's death. Quartinus himself was dismissed from the army by Maximinus after Alexander's death.

But later, Macedo betrayed Quartinus, killed him, and presented his head to Maximinus. Maximinus had Macedo executed nevertheless.

Quartinus story was written down by historian Herodianus. No other independent source mentions him, however, and thus some scholars believe Quartinus is purely an invention of Herodianus.