The chair of the CQC steps down to become parliamentary Under Secretary of State at the Department of Health.
David Prior will take up his new post with immediate effect and Michael Mire, a current CQC board member will chair next weeks board meeting.
He will replace Lord Howe at the Department of Health.
Mr Prior said: 'I am enormously excited about this appointment. However, it is a bittersweet moment for me because I have loved working at CQC for the last two and a half years. It has been a great privilege to work with so many talented staff who are committed to improving the lives of people who use health and care services. I believe that the new regulatory model we have developed will not just identify poor care, but will also stimulat and encourage services to improve.'
Health secretary Jeremy Hunt will appoint Mr Prior's replacement in due course.
Mr Prior became CQC chair in January 2013 after a position as chair of Norfolk and Norwich University Hospital NHS Foundation Trust between 2002 and 2013. He was a Conservative MP until 2001.