Birmingham secured their first home league win of the season thanks to Olivier Kapo's close-range effort.
Olivier Kapo (r) was a constant danger up front for Birmingham
The excellent Sebastian Larsson clipped in a pin-point cross for the unmarked Kapo, who stretched to poke home.
The hosts were rarely troubled by a lacklustre Bolton side whose best chance was a Daniel Braaten run and shot that was blocked by Stephen Kelly.
Larsson hit the bar from a free-kick and despite a late siege on their goal, the Blues held out for a deserved win.
The result leaves under-pressure Bolton boss Sammy Lee still chasing his first away win of the season and languishing in the bottom three. Birmingham, though, recorded a much-needed win and their first clean sheet of the campaign.
Birmingham manager Steve Bruce made three changes from the side beaten at Middlesbrough a fortnight ago with Franck Queudrue, Gary McSheffrey and Mehdi Nafti recalled in place of Radhi Jaidi, Stuart Parnaby and Mikael Forssell.
And the changes invigorated the hosts who adopted a more lively tempo and seldom looked like conceding.
Jussi Jaaskelainen was forced to turn a glancing header from Fabrice Muamba around the post from a Larsson free-kick, while the ever-threatening Swede saw a shot from the right-hand edge of the box well blocked by Abdoulaye Meite.
Skipper Kevin Nolan scuffed a shot wide from 15 yards out and looped a header over the bar from similar range as Bolton toiled.
And the visitors' best chance of the half fell to Jlloyd Samuel who jinked past three weak challenges in the Blues box before smashing his shot straight at Maik Taylor.
Bolton's defensive deficiencies were exposed when Larsson clipped in a delightful cross for Kapo, who poked home his second goal of the season at the back post.
Wanderers improved marginally after the break but lacked the creative spark to unlock the tireless Birmingham back line.
Johan Djourou and Liam Ridgewell stifled the Premier League's leading goalscorer Nicolas Anelka and although El Hadji Diouf was industrious, he rarely threatened where it mattered.
Substitute Braaten opened up the Birmingham defence midway through the second half and but for Kelly's heroic last-ditch tackle, the Norwegian midfielder would have levelled.
Larsson was denied a deserved place on the scoresheet when his sublime free-kick smashed the underside of the bar. And Djourou's header from a corner was cleared off the line by Gavin McCann as Birmingham looked to kill Bolton off.
The second didn't come, but the Blues' hardworking defence repelled a late surge to secure their first league win in front of the St Andrew's crowd.
Birmingham boss Steve Bruce:
"It has been a long time coming but it was well deserved. There was urgency and concentration about us today and I was delighted.
"We were competitive and had good energy about us. With a bit more luck it could have been a comfortable win.
"We had the competitive edge and that made us hard to beat. We had a good crowd in today and that helped a lot."
Bolton boss Sammy Lee:
"I can't take many positives out of this game at all. It was the most disappointing performance of the season so far.
"I don't feel we ever really started today. In the past I have been able to take something from the game, but I can't do that today.
"I'm not looking for excuses and we need to get results quickly."
Birmingham: Maik Taylor, Kelly, Djourou, Ridgewell, Queudrue, Larsson, Muamba (Melendez 87), Nafti, McSheffrey (Schmitz 90), Kapo, Jerome (O'Connor 90).
Subs Not Used: Kingson, Forssell.
Goals: Kapo 37.
Bolton: Jaaskelainen, Hunt, Meite, Andrew O'Brien (Cid 77), Samuel (Gardner 73), Nolan, Speed, Alonso (Braaten 54), McCann, Diouf, Anelka.
Subs Not Used: Al Habsi, Davies.
Booked: Nolan, Speed, Andrew O'Brien.
Ref: Phil Dowd (Staffordshire).