Police said the SUV was left running with the boy inside when it was stolen late Monday afternoon in the 3300 block of 37th Street West.
The boy realized what was happening and jumped out of the moving SUV shortly after it was stolen, police said. He was not injured.
The SUV headed north out of the city, making it up to the Osler area, before turning around and heading back into Saskatoon, police reported.
A tire deflation device was used by officers as the SUV entered the city, police said, and the vehicle stopped in the 100 block of Marquis Drive.
The driver then fled across a parking lot, and police said he was taken into custody after members of the public directed them to him.
Charges are pending as police continue to investigate.
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