Conte survived the second crucial vote of confidence in parliament, but his coalition government was left weakened after it failed to secure an overall majority.
The premier won by 156 votes to 140 in the Senate, but fell short of the absolute majority of 161.
The ruling coalition has been teetering on collapse since former prime minister Matteo Renzi withdrew his Italia Viva party last week.
Conte has been desperately seeking the backing of opposition lawmakers to allow his coalition government, formed in 2019, to stay in power.
“The government has also got the confidence of the Senate. Now the goal is to make this majority even more solid. Italy doesn’t have a minute to lose,” Conte tweeted on Tuesday night, shortly after the vote.
Although the possibility of snap elections appears to be averted, at least for now, Conte’s minority government has been weakened, and will be more vulnerable to attacks from the right-wing opposition in the future.
In both speeches to the Chamber of Deputies and Senate, Conte appealed for support from lawmakers from “the highest European tradition – liberal, popular and socialist”.
Conte’s coalition is made up of the former anti-establishment Five Star Movement (M5S), the centre-left Democratic Party (PD) and a smaller leftist party.
Conte will hope over the coming weeks to persuade some Christian Democrat, conservative and socialist lawmakers, as well as former M5S members and defectors from Renzi’s side, to join them.
Meanwhile, opposition parties said they plan to ask Italian President Sergio Mattarella to intervene to force him to resign.
