While the Brazilian celebrated before a sellout 160,000-strong crowd, his world champion team mate Michael Schumacher [ Images ] was lapped in the first race he has finished without scoring a point for five years.
It was Barrichello's second win in a row, and ninth of a career spent largely in Schumacher's shadow, and gave China a winner in red as the gleaming $325 million Shanghai circuit made its Grand Prix debut.
"I had a very good start and I was amazed by the grip on the first lap...I was feeling good the whole way through," said the Brazilian, second place in the championship now assured behind Schumacher who won his seventh title last month.
Schumacher has 136 points, Barrichello 108 and Button 79.
Spain's Fernando Alonso [ Images ] was fourth for Renault [ Images ], ahead of Colombian Juan Pablo Montoya [ Images ] for Williams and Japan's [ Images ] Takuma Sato [ Images ] in sixth for BAR after starting 18th.
"It was really nice. Towards the end, because I had an eight-second gap, I didn't push that much," said Barrichello, who drenched the elegantly suited Ferrari president Luca di Montezemolo with champagne on the podium before pouring the remainder over his own head.
His race from pole position to chequered flag stood out in marked contrast to Schumacher's unhappy afternoon.
The German finished 12th and was lapped for the first time since the Hungarian Grand Prix of August 2003.
"Certainly it was not my weekend," he said. "But I have had so many good weekends this year and we have still won the Grand Prix with Rubens and those are the important factors."
The last time Schumacher, who has retired from just one race this year, had finished a Grand Prix without scoring points was Australia [ Images ] in 1999 when he came eighth and the scoring system was different.
After spinning out in the worst qualifying performance of his career on Saturday and starting from the pitlane, the winner of 12 of the season's first 13 races banged wheels with Jaguar's Christian Klien on lap 12.
A spin three laps later pushed him back from 11th to 12th place and his frustration was compounded by a puncture 20 laps from the end.
Button ran a two-stop strategy, compared to the other front-runners' three, which made his third place in qualifying even more impressive.
His points, and Sato's fine effort, enabled BAR to pull nine points clear of Renault in the battle for overall second place with two races remaining.
Ferrari, who have already won the constructors' championship, have 244 points to BAR's 105. Renault have 96.
"It was a very tough race," said Button, celebrating his ninth podium of the year and fourth second place, who lost two places at the start as Alonso and Massa powered past.
"When you know the other guys are doing a three-stop and you're doing a two it does make it very difficult mentally because you've got so much weight on board."
Canadian Jacques Villeneuve, racing for the first time in almost a year as a replacement for Italian Jarno Trulli [ Images ] at Renault, was 11th.
Germany's [ Images ] Ralf Schumacher, also returning after a six-race absence following his crash at Indianapolis in June, retired.
Ralf picked up a puncture and feared damage after colliding with David Coulthard's [ Images ] McLaren, but he pitted right before team mate Juan Pablo Montoya was due to come in.
"Since we didn't know whether his car had been damaged, we refuelled and changed tyres on Juan's car first," said BMW [ Images ] motorsport director Mario Theissen.
"When it became clear that Ralf had only a puncture, it was too late to send him out again."