He defeated Democratic challenger Amy McGrath in what had been a target seat.
In 2016 the district backed Trump by 55 to 39 percent.
This is a significant blow to the Democrats who had hopes of taking the seat.
Earlier this evening Washington based journalist Alexandra von Nahmen tweeted: “Keeping an eye on the race in the sixth congressional district in Kentucky.
“If Amy McGrath manages to unseat the Republican incumbent there this will provide an indication into whether the blue wave is on.”
Mr Barr has represented Kentucky’s 6th district since 2013.
His opponent, Ms McGrath, was the first female Marine to fly an FA18 on a combat mission.
More to follow…