Ivan Hadzhinikolov (December 24, 1869, Kilkis, Ottoman Empire - July 9, 1934, Sofia, Bulgaria) was a Bulgarian revolutionary from Macedonia, leader of the revolutionary movement in Macedonia, Eastern and Western Thrace. He was among the founders of the Bulgarian Macedonian-Adrianople Revolutionary Committees in October 1893 (the organization was renamed to IMARO in 1906 and IMRO in 1920). He is considered an ethnic Macedonian in the Republic of Macedonia.
He received elementary and secondary education in Kilkis, Plovdiv and Svishtov. Then Hadzhinikolov graduated higher education at commerce in Linz. After that he worked as a Bulgarian teacher in Kostenets, Edessa, Kilkis and Thessaloniki.
Ivan Hadzhinikolov opened a bookstore in Thessaloniki in 1893 after leaving the school. The IMARO was founded in his house in 1893. In 1901 he was arrested and sent into exile in Bodrum Castle in Asia Minor. After amnesty in 1903 Hadzhinikolov went to Sofia and was engaged in booktrade and commerce. After a heavy illness with disordered nerves hе commitеd suicide in 1934.