| Club: | Dumbarton |
| Season: | 2004-05 |
| Manager: | Brian Fairlie/Paul Martin |
| Stadium: | Strathclyde Homes Stadium, Dumbarton |
| League: | Scottish League Division 2 |
| League Result: | 7th |
| Cup1: | Scottish Cup |
| Cup1 Result: | First Round |
| Cup2: | Scottish League Cup |
| Cup2 Result: | Second Round |
| Cup3: | Bell's Challenge Cup |
| Cup3 Result: | First Round |
| Matches: | 41 |
| Total Goals: | 50 |
| League Topscorer: | Iain Russell (11) |
| Season Topscorer: | Iain Russell (13) |
| Highest Attendance: | 1,446 |
| Lowest Attendance: | 522 |
| Average Attendance: | 900 |
| Prevseason: | 2003–04 |
| Nextseason: | 2005–06 |
Season 2004–05 was the 121st football season in which Dumbarton competed at a Scottish national level, entering the Scottish Football League for the 99th time, the Scottish Cup for the 110th time, the Scottish League Cup for the 58th time and the Scottish Challenge Cup for the 14th time.
The near miss in gaining promotion the previous season had ensured that there was considerable confidence in the team going into season 2004-05 to make that further step. However, despite a successful opening spell, results were not as good as anticipated, and in December Brian Fairlie would make way for Paul Martin in the manager's seat. There was to be no great resurgence in results and in the end a disappointing 7th place was achieved.
In the Scottish Cup, after defeating Cowdenbeath in the first round, it would be Berwick Rangers that would advance from the second round tie, after a drawn match.
In the League Cup, Ross County would prove to be too strong in the first round.
Finally, in the Scottish Challenge Cup, it was another first round exit, this time to Stirling Albion.
Locally, in the Stirlingshire Cup, Dumbarton won one and lost one of their opening group ties, and would take no further part in the competition.
See main article: 2004–05 Scottish Second Division.
See main article: 2004–05 Scottish Challenge Cup.
See main article: 2004–05 Scottish League Cup.
See main article: 2004–05 Scottish Cup.
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| Player | From | Date | |
|---|---|---|---|
| Derek Allan | Queen of the South | 24 May 2004 | |
| Ryan Borris | St Peters Juv | 7 Jun 2004 | |
| Robert Dunn | St Mirren | 7 Jun 2004 | |
| Dundee United (loan) | 27 Aug 2004 | ||
| Eddie Annand | St Mirren | 28 Aug 2004 | |
| Karl Anderson | St Mirren | 1 Sep 2004 | |
| Chris McGroarty | Airdrie United | 23 Sep 2004 | |
| James Allan | Stirling Albion | 22 Jan 2005 | |
| John Gemmell | Partick Thistle | 26 Jan 2005 | |
| Robert Walker | Hamilton | 30 Jan 2005 | |
| Mark Dempsie | St Mirren | 9 Feb 2005 |
| Player | To | Date | |
|---|---|---|---|
| Neil Collins | Sunderland | 12 Aug 2004 | |
| Chris McGroarty | 31 Dec 2004 | ||
| Steven Bonar | Forfar Athletic | 15 Jan 2005 | |
| Robert Dunn | Stirling Albion | 21 Jan 2005 | |
| Derek Allan | 24 Jan 2005 | ||
| Steve Renicks | Bellshill Athletic | ||
| Gordon Herd | Berwick Rangers | ||
 Bjorn Skjelbred | FK Eik Tønsberg | ||
| Steve Laidler | Farnborough Town |