The scandal-tainted 75-year-old prime minister was forced to turn to parliament to confirm its support when the government was defeated by just one vote when it tried to pass a significant part of the 2010 budget.
Berlusconi is expected to survive the vote, but the margin is likely to be small.
Ahead of the vote, the prime minister told parliament there was no alternative to his government.
“Early elections would not solve the problems we have,” he said. “A political crisis now would mean victory for the party of decline, catastrophe and speculation.”
The defeat in parliament has revived talks of possible plots against an embattled Berlusconi from within the government’s own ranks.
His former ally, ex-economic minister Claudio Scajola has begun voicing discontent and there are rumours over the allegiance of Finance Minister Giulio Tremonti.
Berlusconi’s popularity is at an all-time low with the latest poll last month giving him a 24 per cent approval rating.
He is also currently a defendant in trials for bribery, tax fraud, abuse of power and paying for sex with a 17-year-old girl.
Political uncertainty and its effect on long-term economic policymaking was cited as a key factor for the recent downgrades of its sovereign debt by rating agencies Standard & Poor, Fitch and Moody’s.