Fiji were crowned the first men's Olympic sevens champions after crushing Britain 43-7 in the final of the inaugural tournament in Rio.
Bainimarama attended every day of the three-day competition, shunning the VIP area to sit with Fijian fans in the stands.
Speaking after his country claimed gold, the prime minister said there would be at least one more day of public holiday after three this week.
"They're all celebrating (back home), they've been celebrating for the last three days," he told reporters.
"We've got celebrations programmed for when (the team) return ... We are all proud to be Fijians right now."
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With a population of around 900,000, Fiji has long punched above its weight in international rugby, particularly in the sevens game which rewards the pace, power and skill of its distinctive brand of play.
Bainimarama said the inclusion of rugby in the Olympics this year for the first time since 1924 had "propped up" smaller nations like his.
Referring to Fiji's previous rugby triumphs, including back-to-back wins at the world series in the last two years, he said: "They were not like this one, this is the Olympics."
He also hinted there would be rewards for Fiji's players and British coach Ben Ryan but hoped his country would soon get back to work after the appropriate amount of celebrating.
"Our productivity has been nil in the last couple of days, but hopefully the GDP will go in up in the next couple of weeks," he said.
