The Argentine capital has been in party mode since their dramatic victory over France in Sunday's final in Qatar, which gave the country its first World Cup win since Diego Maradona hoisted the trophy 36 years ago.
The players, wearing their gold winners' medals around their necks and taking turns to hold the World Cup trophy aloft, waved at fans from an open-top bus as the lights from thousands of mobile phones sparkled and flags fluttered in the crowd.
Joyous fans sang to the beat of a drum and fireworks lit up the sky as the bus slowly wound its way through the crowd.
The players are expected to spend a few hours at the Argentine Football Association (AFA) facilities near the airport before heading at noon to the huge Obeliso monument in the centre of town.
"Good morning!" Messi said on Tuesday in an Instagram post in which he could be seen sleeping in his room at the AFA complex next to the golden trophy.
Local media estimated that there were already more than 100,000 people waiting for the players at the Obeliso by mid-morning, with more crowds joining from streets on all sides.
Thousands had tracked the plane, the state airline Aerolineas Argentinas AR1915, all the way from Doha and a stop-off in Rome.
Argentina beat France 4-2 on penalties after a scintillating 3-3 draw, with Messi scoring twice and France's Kylian Mbappe netting three times.
Messi said the final would be his last match in the World Cup, though he intends to play a few more games for the national side.
