Alkis Konstantinidis/Reuters
Tsipras, who controls 149 lawmakers from his leftist Syriza party, won the backing of 162 deputies in the 300-seat parliament with the support of his junior coalition partner, the right-wing, anti-bailout Independent Greeks party.
The vote comes before crunch meetings of euro zone finance ministers on Wednesday and EU leaders on Thursday to discuss Greece's future amid rising alarm at the risk of a Greek exit from the euro that could trigger wider financial instability.
(Reporting by Lefteris Papadimas, Costas Pitas and Karolina Tagaris, Writing by Deepa Babington)