Leo Tornikios (Greek: Λέων Τορνίκιος) was a mid-11th century Byzantine general and noble. In 1047, he rebelled against his cousin, the Byzantine Emperor, Constantine IX Monomachos (r. 1042–1055). He raised an army in Thrace and marched on the capital, Constantinople, which he besieged. After two failed assaults he withdrew, his army deserted him and he was captured. At Christmas 1047, he was blinded and no more is known of him.