The measures include a three-year salary freeze for public workers, a 10 per cent cut in ministry budgets, less funding for local government and more action to combat tax evasion, among other measures.
Supporters say the moves are necessary to keep market turmoil affecting Greece, Portugal and Spain from spreading to Italy, amid Europe's worsening debt crisis.
"The approval of the package was necessary," Berlusconi said at a news conference on Wednesday.
"If it was not approved, international speculation would have been unleashed on our country, creating a situation not like that of Greece but still bloody and dangerous."
Italy's largest union staged strikes over the measures, as did magistrates, doctors and diplomats, although the protests have been minor compared with those in Greece.
While unpopular with much of the population, the austerity package has won praise from European Union officials and the International Monetary Fund (IMF).
In what could be considered a sign of the times, Italian officials are seeking to raise $32m in private money to restore one of the country's historic landmarks: the Colosseum.
The culture ministry says the government will accept sponsors seeking to "promote their image" on the iconic structure but any advertisements will have to be compatible with the decorum of the 2,000-year-old arena.