Const. Rick Wolfe with the Winkler Police Service says the boy was between five and ten-years-old and had been part of the float crew at the annual Winkler Heritage Festival parade on Saturday.
Wolfe says the boy was from the Winkler area and was listed in stable condition after the incident.
STARS Air Ambulance spokesman Colin Fast says it appears the boy was on the float at one point, but may have gotten off to either accept, or give out, candy.
Fast says he was run over by the float that was being pulled on a seven-metre trailer.
Last weekend, Rueshad Grant, 18, died when police say he was run over while standing by a parade float in Toronto's Caribbean Carnival.
A boy also last month died after being run over by a float at the end of a Fourth of July parade in Oklahoma.
In July 2012, an eight-year-old boy died after being run over by a float in a parade celebrating the centennial of Preeceville, Sask.