The Serbia international has taken time to adjust to the Premier League after his £6million summer move from Valencia, but he followed up his goal at Arsenal last weekend with the decisive second against the Tangerines after Liam Ridgewell had opened the scoring.
It enabled Blues to end a run of six league games without a win and find the net in front of their own fans for the first time since August 21. The victory was Alex McLeish's 50th win as Birmingham manager.
City were well worth their second victory of the campaign with Zigic starting to adapt to the top flight after a testing start and linking up well with the midfield.
Alexander Hleb also had his best game since arriving on loan from Barcelona and made several incisive passes and probing runs.
Barry Ferguson also gave another exemplary performance in the centre of the park.
Blackpool deserve credit for continuing to show a positive attitude away from Bloomfield Road but they have now conceded 20 goals in nine Premier League games.
Blackpool started brightly and Gary Taylor-Fletcher directed a header straight a Ben Foster from Neal Eardley's right-wing cross.
City retaliated and Eardley was yellow carded after four minutes for clipping the heels of Keith Fahey after he ran onto a pass from Hleb.
Blackpool keeper Matthew Gilks was forced to tip over the resulting 20-yard free-kick from Sebastian Larsson.
Zigic then deflected goalwards a low drive from Larsson but Gilks got his body behind the effort.
Blackpool appealed in vain for a penalty after a corner from David Vaughan bounced up off the pitch and struck the arm of Ridgewell.
The visitors looked vulnerable at the back and another telling pass from Hleb sent O'Connor clear of their defence.
But Craig Cathcart made up several yards to deny O'Connor with a fine tackle as he prepared to shoot.
The game was flowing from end to end and former Birmingham striker DJ Campbell forced Foster to save low to his left.
O'Connor had the ball in the net after 32 minutes but had strayed a yard offside.
Stephen Carr and fellow full-back Ridgewell were getting forward to good effect - and it was the latter who broke the deadlock after 36 minutes.
Larsson's deep corner was initially headed back across goal by Ridgewell, and when Zigic's header struck the bar Ridgewell was first to react to the rebound and made no mistake from close range.
Zigic had a chance to double City's lead just before the interval after Carr had sent the ball across the box but he failed to make proper contact on his volley.
City defender Scott Dann flung himself forward to make an important block on Luke Varney's shot from the edge of the box early in the second half.
Then after 56 minutes Zigic struck for the second time in two games to double City's lead.
Johnson got on the end of Larsson's corner and the loose ball was knocked back across the area by Ridgewell.
Blackpool skipper Charlie Adam then miscontrolled the ball inside the six-yard box and Zigic took full advantage, firing home into the roof of the net.
Adam was in the thick of the action and had a chance to atone for his error but Foster was the equal of his 15-yard drive.
McLeish brought on Lee Bowyer for Fahey and at the same juncture Holloway replaced Marlon Harewood and the limping Adam with Matt Phillips and Keith Southern.
Southern flashed a shot across the face of goal but the second goal had knocked much of the stuffing out of Blackpool.
Brett Ormerod came on for Varney and the impressive Hleb made way for David Murphy.
Bowyer had the chance to make it 3-0 but sent his left-footed attempt wide from Murphy's cross.
O'Connor had a shot blocked before being replaced by Matt Derbyshire, while a Campbell volleyed was blocked by Dann as Blackpool rallied in the closing stages.