The men swept into action after seeing the Mercedes entering the river at about 10.35am today from the car park of the Conyngham Hall conference venue and business centre in Knaresborough.
They rushed into the water and rescued the 86-year-old driver from the submerged vehicle before he was handed into the care of paramedics.
The man, who is from the Wakefield area of West Yorkshire, suffered cuts and grazes in the incident but was otherwise unhurt.
North Yorkshire Police’s Insp Clive Turner said: “There is no doubt that the men who came to the rescue have saved the man’s life.
“The vehicle ended up completely submerged and without their quick thinking and very brave actions, the outcome could have been tragic.
“Rivers are dangerous bodies of water and the two men risked their own lives in the process.
“We extend a very big thank you to them, they should be extremely proud of what they have done.”