The new deal will keep the 27-year-old skipper at hears until the summer of 2013.
Hearts managed to beat Scottish giants Celtic 2-0 in the Scottish Premier League on Wednesday.
“We had a great result last night against Celtic which followed the win over Hibs on Sunday so it has been a special week for me,” Zaliukas told the Hearts website.
“I am very happy to have signed a new contract with Hearts.
“All I want to do is focus on my football now, keep learning and improving as a player and try to bring more success to Hearts.
“We have had an encouraging start to the league this season but we have to keep the good work going, maintain our momentum and try to keep the pressure on the teams above us.
“St Johnstone will be a tough 90 minutes on Saturday and we don’t want to spoil all the good work which has been done in the last couple of games with a poor result in Perth.”