| U-139 | Type IID |
| Feldpost Number | M 05 132 |
| Construction Yard | Deutsche Werke AG, Kiel-Gaarden |
| Yard Number | 268 |
| Ordered | 25th Sep 1939 |
| Keel laid | 20th Nov 1939 |
| Launched | 28th Jun 1940 |
| Commissioned | 24th Jul 1940 |
| Baubelehrung | Baubelehrung U-Boote Ostsee, Kiel |
| Training, Flotillas and Duties |
| 07.40 - 10.40 | 1.U-Flottille, Kiel Ausbildungsboot (under training)
|
| 10.40 - 04.41 | 21.U-Flottille, Pillau Schulboot (training boat)
|
| 04.41 - 05.45 | 22.U-Flottille, Gotenhafen Schulboot (training boat)
|
| Commanders |
| 07.40 - 12.40 | OL Robert Bartels see also: U-561 U-197 |
| 12.40 - 10.41 | OL Horst Elfe see also: U-93 |
| 10.41 - 05.42 | OL Heinz-Konrad Fenn see also: U-445 |
| 05.42 - 06.42 | OL Albert Lauzemis see also: U-37 U-68 |
| 07.42 - 10.42 | OL Helmut Sommer see also: U-78 U-853 |
| 10.42 - 09.43 | LT Richard Böttcher |
| 09.43 - 12.43 | LT Hubertus Korndörfer see also: U-407 |
| 12.43 - 07.44 | OL Günther Lube see also: U-552 |
| 07.44 - 05.45 | LT Walter Kimmelmann |