Yane Ivanov Sandanski (Bulgarian: Яне Иванов Сандански, Macedonian: Јане Иванов Сандански, romanized: Jane Ivanov Sandanski; Originally spelled in older Bulgarian orthography as Яне Ивановъ Сандански (Yane Ivanov Sandanski); 18 May 1872 – 22 April 1915) was a Macedonian Bulgarian revolutionary and leader of the left-wing of the Internal Macedonian-Adrianople Revolutionary Organisation (IMARO).
In his youth Sandanski was involved in the anti-Ottoman struggle, joining initially the Supreme Macedonian-Adrianople Committee (SMAC), but later switched to IMARO by pledging his loyalty to Gotse Delchev. As an activist of the Liberal Party (Radoslavists), at that time he became the head of the local prison in Dupnitsa. He was the mastermind behind the abduction of American Protestant missionary Ellen Stone in order to secure funds for IMARO. After the Ilinden Uprising, Sandanski became the leader of the Serres revolutionary district and of the socialist inspired left-wing ("federalist") faction of IMARO. With his superior leadership he managed to establish a "state within the state" in northeastern Macedonia. The left-wing advocated for the establishment of an independent Macedonian political entity after the autonomy, and the creation of a Balkan Federation, attaining equality for all its subjects and nationalities. Sandanski and the left-wing also vigorously resisted the idea of unification of Macedonia with Bulgaria. During the Second Constitutional Era he became an Ottoman politician, collaborating with the Young Turks and founding the People's Federative Party. Sandanski took up arms on the side of Bulgaria during the Balkan Wars (1912–13). Afterwards, he became involved in Bulgarian public life again, supporting the Democratic Party, but began plotting to assassinate the Bulgarian Tsar Ferdinand I and was executed by the rivalling IMARO right-wing faction activists on the order of Todor Aleksandrov.