The meeting is the first between the two leaders since protests broke out in the Eastern European country over the controversial re-election of Mr Lukashenko for a sixth term last month.
Mr Lukashenko is visiting Russia in a bid to secure more loans and political support as demonstrations against the extension of his 26-year rule enter a sixth week.
The talks will be held in the Black Sea resort of Sochi - a day after an estimated 150,000 people flooded the streets of the Belarusian capital, Minsk, demanding his resignation.
Belarus' interior ministry said 774 people were arrested in Minsk and other cities around the country for holding unsanctioned rallies on Sunday.
Moscow has promised to send military forces to intervene if the protests escalate.
In a bid to win Moscow's support, Mr Lukashenko - who insists he won 80% of the election vote fairly - has tried to cast the protests as an effort by the West to isolate Russia.
Mr Putin sees neighbouring Belarus as a key bulwark against NATO and a major conduit for energy exports to Europe.
Russia and Belarus have a union treaty envisaging close political, economic and military ties, but they have often engaged in acrimonious disputes.
Before the election, Mr Lukashenko repeatedly accused the Kremlin of pressing Belarus to abandon its independence.
But with the US and the EU criticising the election as neither free nor fair, and readying a package of sanctions, Mr Lukashenko now has to rely squarely on Russia's support.
The Kremlin is thought to fear the prospect of the protests forcing the resignation of Mr Lukashenko, fearing it could embolden Mr Putin's critics at home.
Several of Belarus's outspoken activists have been arrested or forcibly removed from the country.
Last week, opposition leader Maria Kolesnikova said she was forced into a van by masked men in Minsk and driven more than 200 miles to the Ukranian border.
The 38-year-old is in jail in the capital on a charge of undermining national security.
Moscow has also signalled it is ready to discuss the restructuring of Belarus' £772.6 million debt to Russia, a key issue in today's talks between the leaders.