| Club: | Dumbarton |
| Season: | 2008-09 |
| Manager: | Jim Chapman |
| Stadium: | Strathclyde Homes Stadium, Dumbarton |
| League: | Scottish League Division 3 |
| League Result: | 1st |
| Cup1: | Scottish Cup |
| Cup1 Result: | Third Round |
| Cup2: | Scottish League Cup |
| Cup2 Result: | Second Round |
| Cup3: | League Challenge Cup |
| Cup3 Result: | First Round |
| Matches: | 42 |
| Total Goals: | 72 |
| League Topscorer: | Ross Clark (14) |
| Season Topscorer: | Ross Clark (15) |
| Highest Attendance: | 1396 |
| Lowest Attendance: | 462 |
| Average Attendance: | 712 |
| Prevseason: | 2007–08 |
| Nextseason: | 2009–10 |
Season 2008–09 was the 125th football season in which Dumbarton competed at a Scottish national level, entering the Scottish Football League for the 103rd time, the Scottish Cup for the 114th time, the Scottish League Cup for the 62nd time and the Scottish Challenge Cup for the 18th time.
Jim Chapman's first full season in charge began with a large intake of new playing staff. A slow start however was to be replaced by an unbeaten run of 8 games which saw Dumbarton rise to 2nd place by the beginning of November. Mixed results in December through February meant that Dumbarton fell to 4th place, but still in with a playoff chance. However it was to be a final surge which saw 7 wins taken from the last 8 games which pushed Dumbarton to the Third Division title. Indeed that run brought about Dumbarton's record number of consecutive 'shut-outs' - 7 in all.
In the Scottish Cup, a second round victory over Highland League opponents Fraserburgh was followed by a close encounter with First Division Ross County, which was only decided by the odd goal in three and that after a draw.
In the League Cup, Dumbarton defeated Annan Athletic on penalties, but were to be overwhelmed by Premier Division St Mirren in the second round.
Finally, it was yet another League Challenge Cup first round exit, to Airdrie United.
Locally, the Stirlingshire Cup was not competed for.
See main article: 2008–09 Scottish Third Division.
See main article: 2009–10 Scottish Challenge Cup.
See main article: 2008–09 Scottish League Cup.
See main article: 2008–09 Scottish Cup.
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| Player | From | Date | |
|---|---|---|---|
| Mick Dunlop | Queen's Park | 25 May 2008 | |
| Paul Keegan | Partick Thistle | 25 May 2008 | |
| Dave McEwan | Derry City | 28 May 2008 | |
| Iain Chisholm | Albion Rovers | 13 Jun 2008 | |
| Mark McGeown | Ayr United | 13 Jun 2008 | |
| Alan Gourlay | Vale of Leven | 19 Jun 2008 | |
| Ross Clark | Alloa Athletic | 27 Jun 2008 | |
| Stevie Murray | Partick Thistle | 1 Jul 2008 | |
| Derek Carcary | Raith Rovers | 7 Jul 2008 | |
| David Gray | Kilbirnie Ladeside | 7 Jul 2008 | |
| Gary Wilson | Pollok | 7 Jul 2008 | |
| Martin McNiff | Leven Valley Am | 9 Jul 2008 | |
| Ben Gordon | Strathclyde Univ | 22 Jul 2008 | |
| Michael White | Alloa Athletic | 25 Jul 2008 | |
| Steven Weir | Livingston | 9 Aug 2008 | |
| Raymond Logan | Pollok | 26 Aug 2008 | |
| Paul McLeod | Hamilton | 1 Sep 2008 | |
| Alan Cook | St Mirren Youth | 8 Oct 2008 | |
| Nathan Taylor | 17 Jan 2009 | ||
| Ross Forbes | Motherwell (loan) | 23 Jan 2009 | |
| Kieran McAnespie | Morton (loan) | 30 Jan 2009 | |
| Pat Boyle | Everton | 31 Jan 2009 | |
| Ryan McStay | Partick Thistle | 3 Feb 2009 | |
| Denis McLaughlin | Hearts (loan) | 21 Feb 2009 | |
| Paul Craig | Benburb | 3 Mar 2009 |
| Player | To | Date | |
|---|---|---|---|
| David Crawford | Queen's Park | 12 Jun 2008 | |
| Tommy Coyne | Albion Rovers | 15 Jul 2008 | |
| Greg Cavanagh | St Anthonys | 1 Aug 2008 | |
| Kenny Haswell | Kirkintilloch Rob Roy | 1 Aug 2008 | |
| Steven Weir | Arbroath | 21 Aug 2008 | |
| Chris Hamilton | Stirling Albion | 22 Aug 2008 | |
| Alan Gourlay | Vale of Leven | 10 Oct 2008 | |
| Craig Brittain | 2 Jan 2009 | ||
| David Gray | 31 Jan 2009 | ||
| Jason McLaughlin | 31 Jan 2009 | ||
| Liam Cusack | Annan Athletic | 2 Feb 2009 | |
| Michael Moore | Stranraer | 27 Feb 2009 | |
 Axel Orrström | AC Oulu | ||
| David Craig | Arthurlie | ||
| Peter Shaw | Arthurlie | ||
| Brian McPhee | Bathgate Thistle | ||
| Jonathan Yule | Benburb | ||
| Craig Potter | Cumnock | ||
| Chris Gentile | Kirkintilloch Rob Roy | ||
| Paul McQuilken | Kirkintilloch Rob Roy | ||
| Anton Nugent | Kirkintilloch Rob Roy | ||
| David McNaught | Vale of Leven | ||
| Ryan Russell | Vale of Leven | ||
| Richie McKillen | Glenafton Athletic | ||
| Raymond Logan | |||
| Michael Stokes |