Orest-Octavian Martinovich Gabel (c. 1849 — 15 March 1915) was a revolutionary Narodnik, a librarian, and a public figure in Imperial Russia.

He was born in late 1849 in the town of Volochysk, Starokostiantyniv District of the Volyn Governorate in a Polish family of Martin Gabel and his wife Balbina.

His father was an Austrian subject and worked as a pharmacist; besides Orest, the family had two sons, Eduard and Modest, and a daughter, Ludvika.

Gabel was summoned for interrogation, and on June 22 of the same year, the case was closed due to lack of evidence of criminal activity.

Gabel responded to the call of Mikhail Sazhin and, as part of a group of Russian revolutionaries, set out for the Balkans to participate in the anti-Ottoman Bosnia-Herzegovina uprising, fighting in the unit of Peko Pavlovich [sr].

The Gabel group prepared the organisation of the escape of arrested revolutionaries from the House of Preliminary Detention.

On 17 August 1877, Gabel was arrested for his connections with Kovalik and the prisoners of the preliminary detention centre.

At a society meeting on child physical education, which included 200 members, he delivered a report on protecting children from abusive treatment (1901).

That year, in his honour, the meeting of the library's board approved ten subscriptions in Gabel's name free of charge to female students attending advanced courses.