Paul Martin's first full season in charge was not to be a happy one. The league campaign did not start well with only 1 win recorded from the first 9 matches. There was a temporary improvement in results from mid October to mid November, but thereafter success was hard to come by, and from February onwards just 2 draws were salvaged from 13 league encounters, meaning that Dumbarton would be anchored at the bottom of the table and relegation was assured long before the season's end. It also meant the end of Paul Martin's tenure in the manager's seat.
In the Scottish Cup, a first round win over Highland League opponents Forres Mechanics was followed by an embarrassing defeat to Third Division Arbroath.
In the League Cup, it was another first round exit, this time to Hamilton.
Finally, in the Scottish Challenge Cup, Dumbarton's dismal record in this competition was extended by a further year with a second round defeat to Raith Rovers.
Locally, in the Stirlingshire Cup, Dumbarton lost both of their opening group ties, and failed to score too.
Despite the disappointing end, the season had in fact started brightly with an invite to the pre-season Keyline Tournament run by Oban Saints. This was duly won, with 3 wins and 2 draws from 5 matches, against strong opposition including Hearts, Dundee United and St Johnstone.
Source: "2005-2006 Second Division - SPFL Archive". SPFL. Retrieved 29 April 2021. Rules for classification: 1) points; 2) goal difference; 3) number of goals scored. (R) Relegated Notes:
^The 9th placed team were entered into a play-off with the Third Division's 2nd, 3rd and 4th placed teams. The winning team were awarded a place in the 2006–07 Second Division, Alloa Athletic won the play-off to stay in the division.
The League match against Peterhead on 29 October marked Iain Russell's 100th appearance for Dumbarton in all national competitions - the 128th Dumbarton player to reach this milestone.