Beaten in its first three matches, Derby ended that barren run thanks to the Manchester United legend.
Derby captain Rooney curled home a free-kick from just outside the area in the 87th minute, rolling back the years to his halcyon days at United.
It was rough justice on the Canaries, who dominated for long periods and wasted a guilt-edged chance to go ahead in the second half when Teemu Pukki missed a penalty after slipping on the rain-soaked turf.
Relegated Norwich has now lost twice in a row after taking four points from its opening two games.
"I knew it was a great chance, especially with a player like Wayne to take it. As everyone knows our captain has great quality and he showed that with his free-kick," Derby boss Phillip Cocu said.
"He had put in a lot a hard work for the team and we were about to take him off but I was certainly glad he was on the pitch when we were awarded the free-kick!"
Elsewhere, Reading extended its 100 per cent start to the second tier season with a 1-0 win over Watford at Madejski Stadium.
The Royals grabbed the lead in the 41st minute, George Puscas pouncing from close range with a deflected effort.
Reading has won four in a row, while Watford, relegated from the Premier League last season, was beaten for the first time in four games.
Bristol City notched up a fourth consecutive win with a 2-1 success at lowly Nottingham Forest.
Early goals from Andreas Weimann and Nahki Wells were enough to keep Dean Holden's side top of the table with Luke Freeman's spectacular strike no consolation for under pressure Forest boss Sabri Lamouchi.
Swansea climbed to fourth place with a 2-1 victory over Millwall at Liberty Stadium.
Jake Bidwell and Ben Cabango were on target for the hosts in the second half, with the visitors' Tom Bradshaw levelling in between.
Middlesbrough defeated Barnsley 2-1 in manager Neil Warnock's 1500th game, while Luton Town beat struggling Wycombe Wanderers 2-0.
Queens Park Rangers' Macauley Bonne scored deep into stoppage-time to rescue a 1-1 draw at bottom of the table Sheffield Wednesday.
Rotherham United and Huddersfield Town drew 1-1, while Blackburn Rovers and Cardiff City shared the points in a goalless draw.