Pseudo-Constantine Diogenes or Pseudo-Leo Diogenes (died after 1095) was an unsuccessful pretender to the Byzantine throne against Emperor Alexios I Komnenos. Of lowly origin, he pretended to be a son of Emperor Romanos IV Diogenes. Exiled to Cherson, he escaped and took refuge among the Cumans. In 1095, he invaded the Byzantine Empire at the head of a Cuman host and advanced as far as Adrianople before being captured by a ruse and blinded by loyalist forces.