INTERNATIONAL NEWS - Mr Putin was met by Syrian President Bashar al-Assad as he arrived at the Russian Hmeimim airbase, near Latakia.
Russian military support has been crucial in turning the tide of Syria's civil war in Mr Assad's favour.
Mr Putin made a similar withdrawal announcement in March 2016, but Russian military operations continued.
"I order the defence minister and the chief of the general staff to start withdrawing the Russian group of troops to their permanent bases," Mr Putin said on Tuesday, according to the Russian RIA Novosti news agency.
"I have taken a decision: a significant part of the Russian troop contingent located in Syria is returning home to Russia," he added.
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Mr Putin said that if "terrorists raise their heads again", Russia would "carry out such strikes on them which they have never seen".
"We will never forget the victims and losses suffered in the fight against terror both here in Syria and also in Russia," he said.
He told President Assad that Russia wanted to work with Iran, the government's other key ally, and Turkey, which backs the opposition, to help bring peace to Syria.
