The official who could not be named because he was not authorized to speak on the matter said Madonna arrived Sunday at about 2:30 p.m. (1230 GMT; 830 EDT) on Ethiopian Airlines.
Madonna adopted the Malawian-born Mercy this year after she adopted David in 2008.
The official said Madonna would take part in a groundbreaking ceremony for the girls school on Monday.
Madonna's Raising Malawi charity helps care for some of the country's 1 million orphans.
Madonna leaves Malawi after week's charity tour
Oct 31, 2009 9:00 am PDT
Madonna has left Malawi after a nearly weeklong visit with her family, airport and charity officials said Saturday. Officials said Madonna flew out of the southern African country on Friday. The 51-year-old celebrity arrived in the impove...
Madonna promises light for Malawian village
Oct 30, 2009 6:00 am PDT
Madonna has promised electricity to a village in Malawi, the impoverished southern African country where she runs a charity organization and from which she has adopted two children. Speaking in Mphandula, some 50 kilometers (30 miles) fro...
Madonna's New York neighbor sues over noise
Oct 19, 2009 11:15 am PDT
Madonna's Manhattan neighbor has sued her co-op and the building's management company saying the pop star's habit of rehearsing with loud music is a nuisance for other residents. "Madonna and one or more of her invited guest...
NYC neighbor sues Madonna over loud music, dancing
Oct 17, 2009 7:00 am PDT
One of Madonna's New York neighbors says the superstar's loud music and frequent dance sessions are causing a commotion. Karen George, of Manhattan, lives above Madonna in a building on Central Park. She said in a lawsuit filed Friday ag...
Madonna, U2, AC/DC lead Touring Awards finalists
Oct 15, 2009 5:00 pm PDT
Madonna, U2 and AC/DC are among the finalists for the 2009 Billboard Touring Awards, which are based on global box-office numbers reported to Billboard Boxscore from October 1, 2008, through September 30, 2009. The awards will be presente...