The Wales international, who came through the Cardiff academy, headed home from a Mesut Ozil cross in the 29th minute before substitute Mathieu Flamini doubled the lead with five minutes remaining.
Ramsey completed the scoring in stoppage time to make it 15 goals for club and country this season and, as with his first goal, was applauded by both sets of supporters.
Cardiff have enjoyed memorable results against Manchester City, Swansea and Manchester United at Cardiff City Stadium, but Arsenal navigated the potential pitfall with a minimum of fuss and put the pressure on nearest challengers Chelsea and Liverpool, who play on Sunday.
Cardiff, meanwhile, slip to 17th in the table and, despite the good work being done by Malky Mackay, their position will again put his position under scrutiny.
And it was Ramsey who was again the driving force for Arsenal as he and Ozil produced wonderful midfield displays.
Ramsey enjoyed a great reception from the home crowd prior to kick-off, and then almost helped put Arsenal ahead after 70 seconds.
His pass picked out Jack Wilshere, who beat David Marshall with a curling effort which rattled the crossbar.
Arsenal's strong start was punctuated by an injury to Per Mertesacker after the German clashed heads with Bacary Sagna, and Cardiff almost capitalised with the defender on the sidelines having further treatment.
Kevin Theophile-Catherine surged down the right to deliver an inviting cross which Campbell headed wide.
Arsenal should have led in the 15th minute but Olivier Giroud made an embarrassing error.
The French striker thought he was offside when Ozil attempted to flick a through ball on to him - with replays suggesting the B£42million signing had got a touch - and stopped when clean through on goal.
However, assistant referee Lee Betts did not raise his flag and, by the time Giroud had realised, Steven Caulker had got back to make the block, much to the fury of Arsene Wenger.
Ozil's next contribution saw Arsenal take the lead.
His fizzing cross picked out Ramsey's run and the midfielder's header left Marshall with no chance.
Jordon Mutch sent an attempted overhead kick wide from close range but Arsenal were firmly on top and Ramsey could have doubled their lead just before the break.
Giroud picked him out at the far post but he was crowded out by defenders and eventually sent his shot well over the bar.
Another chance arrived seconds into the second half. Ramsey was again at the centre of it, bursting past Peter Whittingham and Kim Bo-kyung to tee up Giroud, only for Ben Turner to block the goalbound effort on the line.
The miss almost proved costly when Kim flicked on a ball into the Arsenal box and Campbell rose to direct a powerful header goalwards, only for Szczesny to make an excellent low save.
The chance prompted a big improvement in Cardiff's play, the hosts upping the tempo and finding a way to disrupt Arsenal's passing patterns.
However, they created little and Arsenal remained a potent threat, with Santi Cazorla hitting a tame effort at Marshall from Wilshere's pass.
Whittingham and Don Cowie worked Szczesny from distance before Flamini slotted home from Ozil's pass for his first Arsenal goal since January 2008, and Ramsey added a third in time added on.
- Sports & Recreation
- Fraizer Campbell
- Wojciech Szczesny
- Mathieu Flamini
- Olivier Giroud