| World Top 10 billionaires in 2009 |
| # | Name | Net Worth(USD) | Age | Citizenship | Sources of wealth |
| 1 | Bill Gates | $40.0 billion | 53 | United States | Microsoft |
| 2 | Warren Buffett | $37.0 billion | 78 | United States | Berkshire Hathaway |
| 3 | Carlos Slim Helú | $35.0 billion | 69 | Mexico | Telmex, América Móvil |
| 4 | Lawrence Ellison | $22.5 billion | 64 | United States | Oracle Corporation |
| 5 | Ingvar Kamprad and family | $22.0 billion | 83 | Sweden | IKEA |
| 6 | Karl Albrecht | $21.5 billion | 89 | Germany | Aldi Süd |
| 7 | Mukesh Ambani | $19.5 billion | 51 | India | Reliance Industries |
| 8 | Lakshmi Mittal | $19.3 billion | 58 | India | Arcelor Mittal |
| 9 | Theo Albrecht | $18.8 billion | 87 | Germany | ALDI Nord, Trader Joe's |
| 10 | Amancio Ortega | $18.3 billion | 73 | Spain | Inditex Group |