The 33-year-old Sawa, competing in her fifth World Cup, led Japan to glory with a penalty shoot-out win in the final against the U.S., and won the Golden Boot as the tournament's leading scorer.
Marta of Brazil and United States striker Abby Wambach were also nominated.
Japan coach Norio Sasaki was named Women's Coach of the Year, ahead of France coach Bruno Bini and the USA's Swedish coach Pia Sundhage.
Argentina's Lionel Messi followed Sawa to win the 2011 FIFA Ballon d'Or, the third consecutive year that he has won the prestigious award for the world's outstanding footballer.
Pep Guardiola, the Spanish coach of FC Barcelona, was the respective winner of the FIFA World Coach of the Year for Men's Football.
Votes were cast by national team coaches and captains, plus invited journalists.
Congratulations, Sawa and Sasaki coach!!
World Best Footballers