Young Turks (Turkish: Jön Türkler or Genç Türkler) was a political reform movement in the early 20th century that favored the replacement of the Ottoman Empire's absolute monarchy with a constitutional government. They led a rebellion against the absolute rule of Sultan Abdulhamid II in the 1908 Young Turk Revolution. With this revolution, the Young Turks helped to establish the Second Constitutional Era in the same year, ushering in an era of multi-party democracy for the first time in the country's history.

Despite working with the Young Ottomans to promulgate a constitution, Abdulhamid II had dissolved the parliament by 1878 and returned to an absolutist regime, marked by extensive use of secret police to silence dissent, and by massacres committed against minorities. Constitutionalist opponents of his regime, most prominently Prince Sabahaddin and Ahmet Rıza, among other intellectuals, came to be known as Young Turks. Despite the name, Young Turks included many Arabs, Albanians, Jews, and initially, Armenians and Greeks. To organize the opposition, forward-thinking medical students Ibrahim Temo, Abdullah Cevdet and others formed a secret organization named the Committee of Ottoman Union (later Committee of Union and Progress - CUP), which grew in size and included exiles, civil servants, and army officers. Finally, in 1908 in the Young Turk Revolution, pro-CUP officers marched on Istanbul, forcing Abdulhamid to restore the constitution. An attempted countercoup resulted in his deposition.

The Young Turks were a heterodox group of secular liberal intellectuals and revolutionaries, united by their opposition to the absolutist regime of Abdulhamid and desire to reinstate the constitution. After the revolution, the Young Turks began to splinter and two main factions formed: more liberal and pro-decentralization Young Turks (including the CUP's original founders) formed the Private Enterprise and Decentralization League, the Ottoman Liberty Party and later the Freedom and Accord Party (also known as the Liberal Union or Liberal Entente). The Turkish nationalist, pro-centralization and radical wing among the Young Turks remained in the Committee of Union and Progress. The groups' power struggle continued until 1913, when the Grand Vizier Mahmut Şevket Pasha was assassinated, allowing the CUP to take over all institutions. The new CUP leadership (Three Pashas) established a one party state and exercised absolute control over the Ottoman Empire, overseeing the Empire's entry into World War I on the side of the Central Powers during the war. The CUP regime also planned and executed the late Ottoman genocides as part of their Turkification policies.

Following the war, the struggle between the two groups of Young Turks revived, with the Freedom and Accord Party regaining control of the Ottoman government and conducting a purge of Unionists with assistance from the Allied powers. The Three Pashas fled into exile. Freedom and Accord rule was short-lived, and with Mustafa Kemal Pasha (Atatürk) stirring up nationalist sentiment in Anatolia, the Empire soon collapsed.

The term "Young Turk" is now used to signify "an insurgent person trying to take control of a situation or organization by force or political maneuver," and various groups in different countries have been named Young Turks because of their rebellious or revolutionary nature. Members of the CUP were known as Unionists, while for most of the world, the Unionists were conflated with the larger Young Turks movement.