Asked how he was feeling as he exited, the 75-year-old former president gave reporters a thumbs up sign.
He left the University of California Irvine Medical Center accompanied by his wife, former Secretary of State and 2016 Democratic presidential nominee Hillary Clinton, who waved before the pair departed in a motorcade of vehicles.
Dr Alpesh Amin, who had been overseeing his care at the hospital, in a statement said Clinton was discharged after his fever and white blood cell count had normalised and would finish his course of antibiotics at home in New York.
We "will continue to monitor his progress," Amin added in the statement released by Clinton's spokesman.
The former president had been in California for an event for his foundation and was treated at medical center's intensive care unit after suffering from fatigue and being admitted on Tuesday.
Clinton, who has had previous heart problems, held the White House from 1993 to 2001. After leaving office, he had quadruple bypass operation in 2004 and a procedure to open a blocked artery in 2010, and has touted his switch to a vegan diet and weight loss.
The Democrat served two four-year terms, overseeing strong economic growth while engaging in bruising political battles with congressional Republicans.
He became the second US president to be impeached after the Republican-controlled House of Representatives impeached him in 1998 on charges arising from his sexual relationship with White House intern Monica Lewinsky, though he was acquitted by the Senate.
A former Arkansas governor, Clinton is known for combining a folksy charm with deep knowledge of policy issues. After his presidency, he and Hillary moved to New York, where she served as US senator before twice launching her own bids for the presidency.