Town made it a magnificent seven home wins of the season with Jon Walters grabbing his first hat-trick for the Club as Blues ran riot at Portman Road.
The wideman opened the goal bonanza on five minutes with David Wright adding a second on 15, his first goal for Town on home soil.
Tommy Miller made it three from the penalty spot a minute into the second-half after Danny Haynes had been brought down inside the box, Bradley Orr sent-off for the challenge.
Walters added a fourth soon after before Pablo Counago got in on the act with a solo finish.
Walters secured the matchball with a third goal, racing onto Counago's pass and leaving Adriano Basso with no chance as Town hit the six mark, the biggest win under Jim Magilton's management and the biggest Blues' victory since the 8-1 win over Avenir Beggen in the UEFA Cup in August 2002.
Counago returned to the starting line-up, with Owen Garvan and Billy Clarke also coming in from the team beaten at Sheffield United in midweek. Alex Bruce keeping his place alongside Jason De Vos at the back.
Garvan's free-kick inside the first minute created an opening for Walters who couldn't take advantage, the wideman then firing wide when clear on the right flank.
Walters made amends on five minutes though, taking Garvan's pass in his stride and cutting inside on his left foot before firing low past Adriano Basso for his fifth goal of the season.
David Noble tested Neil Alexander from 25 yards, Darren Byfield then shooting over from further out as Bristol tried to prise an opening in the Town defence.
Counago lifted the ball over the bar from Alan Lee's head on before Blues extended the lead on the quarter hour, Wright heading in his first goal of the season after Lee's hard work and cross.
Lee tested Basso from the edge of the box as Town threatened to wrap up the points in the first-half.
The Robins' case was helped by an injury to Louis Carey, the skipper forced off midway through the half, Jamie McCombe his replacement.
Marvin Elliott headed over for the visitors, while the dangerous Ivan Sproule was being well marshalled by Dan Harding.
Jamie McAllister was booked for dissent after protesting over a corner, Basso saving at the far post from Lee's header. The Town striker then replaced by Haynes after sustaining what looked like an ankle injury.
Bristol's best chance came just before the break, Michael McIndoe shooting tamely into Alexander's arms after the 'keeper's punch had fallen at his feet.
Enoch Showunmi replaced Noble at the break for City but within 60 seconds the game was all but over, Miller scoring from the penalty spot after Haynes had been taken down inside the box by Orr, the defender shown a straight red by referee Nigel Miller.
Haynes tested Basso with a low drive at the near post as Town threatened to make it four. Brian Wilson replacing Sproule straight after.
The inevitable fourth goal came on 55 minutes, Walters hammering the ball into the net after racing clear on the right flank.
Counago got the goal he deserved on 64 minutes as Town continued to run riot, the Spaniard showing great composure to take Walters' pass into the area and beat two defenders before sidefooting past Basso.
Walters made it six on 72 minutes, Counago setting him up with a sublime pass from deep as the former Chester player completed his hat-trick before making way for Gary Roberts.
Sylvain Legwinski replaced the impressive Garvan for the closing stages, Billy Clarke then wasting a great chance to make it seven, Basso saving from close range after Counago had set him up.
The win makes it 11 on the spin at home and takes Magilton's side closer to the Club record of 15 set 27 years ago. It also takes the goal tally to 23 in seven home games this season.
Town: Alexander, Wright, De Vos, Bruce, Harding, Walters (Roberts 72), Garvan (Legwinski 78), Miller, Clarke, Counago, Lee (Haynes 36). Subs not used: Supple, Wilnis.
Bristol City: Basso, Orr, Fontaine, Carey (McCombe 21), McAllister, Sproule (Wilson 50), Elliott, Johnson, McIndoe, Noble (Showunmi 46), Byfield. Subs not used: Wilson, Trundle, Henderson. Booked: McAllister.
Att: 22, 020