Italian Leoni-Sceti is a 16-year veteran of Reckitt Benckiser and started his career in 1988 as a brand manager at Procter & Gamble before joining the household cleaning goods firm in 1992.
Hands, whose private equity group Terra Firma bought EMI in August 2007 for £2.4bn, will step back to a non-executive role following Leoni-Sceti's appointment.
At Reckitt Benckiser, Leoni-Sceti was promoted to senior vice-president of North American household, and then to executive vice-president of category development in 2001.
In July 2006 he was appointed executive vice-president for Europe and head of the company's £3bn European business, which included overseeing the company's more than £300m European advertising account.
The appointment of Leoni-Sceti completes the management overhaul of EMI, which is home to Cold Play, one of the labels most important acts. Much is hanging on the success of their new album, 'Viva La Vida or Death and All His Friends'.
There had been speculation that Hands would appoint a single chief executive for EMI rather than separate chiefs for EMI Music and EMI Music Publishing.
EMI has struggled since private equity Terra Firma took over, with some artists taking flight, including Paul McCartney and Radiohead.