The crash happened on Monday around 5:30 p.m. on Caribou Road in Shamattawa.
The driver and his two 13-year-old passengers were thrown from the ATV. None was wearing helmets, RCMP said.
The man was pronounced dead at the Shamattawa nursing station. His name has not been released.
Shamattawa is located about 1,300 kilometres north of Winnipeg.
Both of the passengers were taken by air ambulance out of Shamattawa with non-life-threatening injuries.
Police say the driver of the ATV was trying to pass the 2007 GMC Sierra when the crash happened. Alcohol is not believed to be factor, but the investigation continues.
An autopsy will be performed this week in Winnipeg.