His double strike secured the Golden Boot award - and Brazil their fifth World Cup crown.
Ronaldo bounced back to form after the disappointment of a 3-0 final defeat by France four years earlier and subsequent injury troubles.
German goalkeeper Oliver Kahn was voted the tournament's best player despite fumbling Rivaldo's shot to gift Ronaldo an opener.
The final capped a memorable tournament in South Korea and Japan, where England and the Republic of Ireland secured notable successes before elimination.
Skipper David Beckham's penalty saw off old adversaries Argentina as England qualified from the 'Group of Death'.
But his side fell to Brazil in the quarter-finals, with veteran goalkeeper David Seaman blamed for failing to stop Ronaldinho's speculative, looping free-kick winner.
Ronaldinho was later controversially dismissed for a foul, but England could not take advantage in the stifling Shizuoka heat.
Irish hopes suffered an early blow when captain Roy Keane went home after a dramatic bust-up with boss Mick McCarthy.
But another Keane, Robbie, took to the stage and helped fire his side through a tough qualification group which included Germany.
McCarthy's men finally fell in a second round penalty shoot-out against Spain.
Spain went on to suffer their own spot-kick heartache in the quarter-finals, as the march of South Korea continued.
The co-hosts eventually succumbed 1-0 to Germany in the last four, while the other surprise package, Turkey, went down by the same scoreline to Brazil.
Few would have predicted their appearance in the semi-finals, but the early stages claimed several big name casualties.
French boss Roger Lemerre was sacked after the reigning champions and Euro 2000 winners went out following shock losses to Senegal and Denmark.
Argentina's defeat by England hastened their premature exit, while Italy edged though to the second round before enduring a golden goal winner from South Korea's Ahn Jung-Hwan.
Korea's march onto the footballing map helped maintain a carnival atmosphere at matches, where even England's notorious hooligans were absent.
More than three million people took to the streets of Korean capital Seoul to celebrate the defeat of Italy.
And at the World Cup's conclusion, organisers were toasting a successful event which Germany will do well to better when hosting the next finals in 2006.