The son of a peasant, Michael worked as a money changer until he was found a job at court by his brother John the Orphanotrophos. He caught the eye of the empress Zoë Porphyrogenita and they began a tempestuous and flagrant affair. It is believed that they conspired to murder her husband, Emperor Romanos III Argyros, who died in 1034. Michael and Zoë were married the same day and Michael was crowned emperor the day after.

Michael, handsome and energetic, had poor health and entrusted most of the business of government to his brother. He distrusted Zoë and went to lengths to ensure that he did not suffer the same fate as his predecessor. The fortunes of the Empire under Michael's reign were mixed. His most triumphant moment came in 1041 when he led the imperial army against Bulgarian rebels. He returned from this victory, but died a few months later.