The former cardiologist served less than two years of a four-year sentence after being convicted in November 2011 of involuntary manslaughter.
Jail records confirmed Murray's release and the sheriff's office said he left a Los Angeles jail at 12:01 on Monday.
Jackson died on 25 June 2009 after receiving a lethal dose of the anaesthetic propofol from Murray.
The singer had been out of the public eye for several years but was preparing for a series of comeback performances at the O2 arena in London and Murray was serving as his personal physician.
Murray, 60, had been sentenced to serve four years behind bars, but a change in California law allowed his jail term to be significantly reduced.
The former doctor's medical licences remain suspended or revoked in the US states where he previously practised medicine.
According to ABC News, Murray's legal team is filing petitions in Texas to have his medical licence reinstated.