Quintus Hortensius (114 - 50 BC), surnamed Hortalus, was a Roman orator and advocate.

At the age of nineteen he made his first speech at the bar, and shortly afterwards successfully defended Nicomedes III of Bithynia, one of Rome's dependants in the East, who had been deprived of his throne by his brother. From that time his reputation as an advocate was established. As the son-in-law of Q. Lutatius Catulus he was attached to the aristocratic party. During Sulla's ascendancy the courts of law were under the control of the senate, the judges being themselves senators.

To this circumstance perhaps, as well as to his own merits, Hortensius may have been indebted for much of his success. Many of his clients were the governors of provinces which they were accused of having plundered. Such men were sure to find themselves brought before a friendly, not to say a corrupt, tribunal, and Hortensius, according to Cicero (Div. in Caecil. 7), was not ashamed to avail himself of this advantage. Having served during two campaigns (90-89) in the Social War, he became quaestor in 81, aedile in 75, praetor in 72, and consul in 69. In the year before his consulship he came into collision with Cicero in the case of Verres, and from that time his supremacy at the bar was lost.

After 63 Cicero was himself drawn towards the party to which Hortensius belonged. Consequently, in political cases, the two men were often engaged on the same side (e.g. in defence of Rabirius, Murena, Publius Cornelius Sulla, and Milo). After Pompey's return from the East in 61, Hortensius withdrew from public life and devoted himself to his profession. In 50, the year of his death, he successfully defended Appius Claudius Pulcher when accused of treason and corrupt practices by P. Cornelius Dolabella, afterwards Cicero's son-in-law.

Hortensius's speeches are not extant. His oratory, according to Cicero, was of the Asiatic style, a florid rhetoric, better to hear than to read. He had a wonderfully tenacious memory (Cicero, Brutus, 88, 95), and could retain every single point in his opponent's argument. His action was highly artificial, and his manner of folding his toga was noted by tragic actors of the day (Macrobius, Sat. iii. 13. 4). He also possessed a fine musical voice, which he could skilfully command. The vast wealth he had accumulated he spent on splendid villas, parks, fish-ponds and costly entertainments. He was the first to introduce peacocks as a table delicacy at Rome. He was a great buyer of wine, pictures and works of art. He wrote a treatise on general questions of oratory, erotic poems (Ovid, Tristia, ii. 441), and an Annales, which gained him considerable reputation as an historian (Yell. Pat. ii. 16. 3).

His daughter Hortensia was also a successful orator. In 42 she spoke against the imposition of a special tax on wealthy Roman matrons with such success that part of it was remitted (Quint. Instit. i. 1. 6; Val. Max. viii. 3. 3).

In addition to Cicero (passim), see Dio Cassius xxxviii. 16, xxxix. 37; Pliny, Nat. Hist. ix. 8i, x. 23, xiv. 17, xxxv. 40; Varro, R.R. iii. 13. 17.