Spirit had sales of 205,000 copies in its first week.
It means The X Factor winner is the first British solo artist to go straight to No1 in America with a debut album.
Leona, 23, trounced the opposition - her nearest rival George Strait only sold 59,000 copies of his record Troubadour, reports the BBC.
It comes 3 weeks after Bleeding Love took the top spot in the American singles chart.
The last British woman to have a US No1 album was Sade with Promise in 1986.