The vote of no-confidence in Zeidan came after a tanker laden with oil from a rebel-held terminal in eastern Libya broke through a naval blockade and escaped to sea despite his government's threats to block it by force if necessary.
"The Congress voted to withdraw its confidence in the prime minister by 124 votes," MP Suleiman al-Zubi told AFP.
Defense Minister Abdullah al-Thani was named interim premier for the two weeks that General National Congress now has to agree on a permanent replacement, he added.
Previous attempts to bring down Zeidan had failed to win the required majority of 120 of the GNC's 194 members.
Ouster of Libya’s prime minister and its replacement with the defense minister marks the second country revoked by the Arab Spring, standing after Egypt, in which the leader was replaced with a military chief before ending legal term in office.
In July 3, 2013, Egyptian army headed by Defense Minister Abdel Fattah al-Sisi ousted democratically elected president Mohamed Morsi after only a year in office.
SHI/SHI