| Club: | Dumbarton |
| Season: | 1999–2000 |
| Manager: | Jimmy Brown |
| Stadium: | Boghead Park, Dumbarton |
| League: | Scottish League Division 3 |
| League Result: | 6th |
| Cup1 Result: | Second Round |
| Cup2 Result: | First Round |
| Cup3 Result: | First Round |
| Matches: | 40 |
| Total Goals: | 56 |
| League Topscorer: | Paddy Flannery (14) |
| Season Topscorer: | Paddy Flannery (16) |
| Highest Attendance: | 3,031 |
| Lowest Attendance: | 324 |
| Average Attendance: | 581 |
| Prevseason: | 1998–99 |
| Nextseason: | 2000–01 |
Season 1999–2000 was the 116th football season in which Dumbarton competed at a Scottish national level, entering the Scottish Football League for the 94th time, the Scottish Cup for the 105th time, the Scottish League Cup for the 53rd time and the Scottish Challenge Cup for the ninth time.
Season 1999-2000 would be one of the most memorable for Dumbarton, but not because of any titles won or lost, but because this would be the last season that the club would play at their famous Boghead Park. Dumbarton's home had been here for the past 121 years - the longest that any British football club had stayed at any home ground. Now the ground had been sold and Dumbarton would move to a new purpose built stadium at the foot of Dumbarton Rock.
The season itself was unremarkable. Three promotion places were up for grabs due to the addition of Elgin City and Peterhead the following season, however despite an encouraging start there was never a real chance of a top three finish and in the end a midtable 6th place was achieved. It would be the final game however that would define the whole campaign. As it was a crowd in excess of 3,000 turned out to bid farewell to the old ground and with it a fine victory over promoted East Fife.
In the national cup competitions, there was little to cheer. In the Scottish Cup, Dumbarton lost to Stenhousemuir in the second round.
In the League Cup, after a win over Brechin City, Dundee would easily dispatch Dumbarton in the second round.
With newfound sponsorship, the Scottish Challenge Cup was re-instated, but the same old failures beset Dumbarton - yet another first round defeat, this time to Airdrie.
Locally, in the Stirlingshire Cup, Dumbarton lost their two group ties.
See main article: 1999–2000 Scottish Third Division.
See main article: 1999-2000 Scottish Challenge Cup.
See main article: 1999-2000 Scottish League Cup.
See main article: 1999-2000 Scottish Cup.
| Player | From | Date | |
|---|---|---|---|
| Hugh Ward | East Stirling | 26 May 1999 | |
| Michael Dickie | Dundee | 11 Jun 1999 | |
| Scott McHarg | Partick Thistle | 23 Jun 1999 | |
| Andy Brown | Clydebank | 21 Jul 1999 | |
| John Dillon | Clyde | 30 Jul 1999 | |
| John McCormack | Alloa Athletic | 30 Jul 1999 | |
| Chris Templeman | Dunfermline Athletic (loan) | 17 Sep 1999 | |
| John Bradford | Ayr United (loan) | 23 Oct 1999 | |
| Kevin McCann | Partick Thistle (loan) | 26 Nov 1999 | |
| Dave Stewart | Ayr United | 1 Dec 1999 | |
 Hrienn Hringsson | KA Akureyri | 11 Dec 1999 | |
| Chris Gentile | Dundee United | 25 Feb 2000 | |
| Willie Watters | Stenhousemuir (loan) | 25 Feb 2000 | |
| Steven Bonar | Albion Rovers | 30 Mar 2000 |
| Player | To | Date | |
|---|---|---|---|
| Willie Wilson | Cowdenbeath | 23 Jul 1999 | |
| Chris Ewing | Clydebank | 30 Jul 1999 | |
| Martin Mooney | Stenhousemuir | 31 Jul 1999 | |
| Colin McKinnon | Stenhousemuir | 13 Mar 1999 | |
| Peter Dennison | Vale of Leven | ||
| Stevie Gow | Vale of Leven | ||
| Keith Millar | Oban Saints | ||
| David Reid | Cumnock | ||
| Barry Wilkinson | Cumnock |
Dumbarton played an under 19 team in the Scottish Youth Division B, and with 6 wins and 4 draws from 26 games, finished 9th of 10.