Maradona, who led Argentina to the 1986 World Cup title, has battled cocaine addiction and in recent weeks appeared overweight.
A statement from the Guemes hospital did not specify what Maradona was suffering from, but said his hospitalization was "not related to an addiction to dangerous drugs."
Dr. Alfredo Cahe, Maradona's personal physician, told Radio Mitre the 46-year-old former star was "fine" but "has had problems for some time with food, (alcoholic) drinks and tobacco." Maradona was likely to remain hospitalized for several days, he added.
Maradona's return to a hospital was a reminder of the repeated health problems -- many of them drug-related --- he has faced since retiring from the game in 1997.
Cahe had said just days ago that Maradona had put on weight and smoked too many cigars, and was planning a trip to Switzerland to get himself back into shape.
Television images showed an ambulance pulling up to a back entrance at the hospital. Moments later, Maradona's two teen-age daughters entered the building.
In 2000, Maradona was hospitalized with a severe heart problem while vacationing in Uruguay and tested positive for cocaine before undergoing drug rehabilitation in Cuba.
Four years later, he spent 10 days in intensive care with heart and breathing problems and reentered rehabilitation.
He underwent a stomach-stapling operation in 2005, shedding around 30 kgs (66 lbs) and said he was fully recovered and went on to briefly host his own television program.
Since then, he has played in several promotional soccer games with other retired players from across Latin America.
Maradona was suspended for drugs while playing in Italy in 1991 and kicked out of the 1994 World Cup in the United States after failing a drug test, which he blamed on his coaching team for buying the wrong over-the-counter medicine.
