•
Jürgen Prochnow as (abbr. "", ) and also called "" ("the Old Man") by his crew: A 30-year-old battle-hardened but good-hearted and sympathetic sea veteran, he complains to Werner that most of his crew members are boys. He is openly anti-Nazi, embittered and cynical, being openly critical about how the war is being handled. •
Herbert Grönemeyer as (Ensign) Werner, war correspondent: Naive but honest, he has been sent out to sea with the crew to gather photographs of them in action and report on the voyage. Werner is initially mocked for his lack of experience, and soon learns the true horrors of service on a U-boat. •
Klaus Wennemann as chief engineer ( or LI, Rank: ): A quiet and well-respected man, at age 27, he is the oldest crew member besides the Captain and is tormented by the uncertain fate of his wife, especially after hearing about a
British air raid on
Cologne. As the second most important crewman, he oversees diving operations and makes sure the systems are running correctly. •
Hubertus Bengsch as first watch officer (I. WO, Rank: ): A young, by-the-book officer, he is an ardent
Nazi and a staunch believer in the . He has a condescending attitude and is the only crewman who makes the effort to maintain his proper uniform and trim appearance, while all the others grow their beards in the traditional
U-Bootwaffe fashion. He was raised in some wealth in Mexico by his stepparents, who owned a plantation. His German fiancée died in a British air raid. He spends his days writing his thoughts on military training and leadership for the High Command. When the boat is trapped underwater near Gibraltar, he becomes pessimistic and begins to let go of his adherence to Nazi ideas as he finally stops shaving every day and wearing his proper uniform all the time. •
Martin Semmelrogge as second watch officer (II. WO, Rank: ): A vulgar, comedic officer, he is short, red-haired and speaks with a mild
Berlin dialect. One of his duties is to decode messages from base, using the
Enigma code machine. •
Bernd Tauber as ("Chief Helmsman") Kriechbaum: The navigator and 3rd Watch Officer (III. WO) always slightly skeptical of the Captain and without enthusiasm during the voyage, he shows no anger when a convoy is too far away to be attacked. Kriechbaum has four sons, with another on the way. •
Erwin Leder as ("Chief Mechanic") Johann, also called "" ("The Ghost"): He is obsessed with a near-fetish love for
U-96s engines. Johann suffers a temporary mental breakdown during an attack by two destroyers. He is able to redeem himself by valiantly working to stop water leaks when the boat is trapped underwater near Gibraltar. Speaks
a lower Austrian dialect. •
Martin May as (Senior Cadet) Ullmann: A young officer candidate who has a pregnant
French fiancée (which is considered treason by the French
partisans) and worries about her safety, he is one of the few crew members with whom Werner is able to connect. Werner offers to deliver Ullmann's stack of love letters when Werner is ordered to leave the submarine. •
Heinz Hoenig as (Petty Officer) Hinrich: The radioman, sonar controller and ship's
combat medic gauges speed and direction of targets and enemy destroyers. Hinrich is one of the few crewmen whom the Captain is able to relate to. •
Uwe Ochsenknecht as ("Boatswain") Lamprecht: The severe chief petty officer shows Werner around
U-96, and supervises the firing and reloading of the torpedo tubes. He gets upset after hearing on the radio that the football team most of the crew supports (
FC Schalke 04) are losing a match, and they will "never make the final now". •
Claude-Oliver Rudolph as Ario: The burly mechanic who tells everyone that Dufte is marrying an ugly woman, and throws pictures around of Dufte's fiancée in order to laugh at them both also has a disdainful relationship towards the Bibelforscher, as evidenced throughout the miniseries. •
Jan Fedder as (Petty Officer) Pilgrim: Another sailor (watch officer and diving planes operator) who gets almost swept off the submarine during a storm – a genuine accident during filming in which Fedder broke several ribs and was hospitalised for a while. •
Ralf Richter as (Petty Officer) Frenssen: Pilgrim's best friend. Pilgrim and Frenssen love to trade dirty jokes and stories. • Joachim Bernhard as ("Bible scholar", also the contemporary German term for a member of
Jehovah's Witnesses): A very young religious sailor who is constantly reading the Bible, he is punched by Frenssen when the submarine is trapped at the bottom of the
Strait of Gibraltar for praying rather than repairing the boat. •
Oliver Stritzel as Schwalle: A tall and well-built blond torpedoman. • Jean-Claude Hoffmann as Benjamin: A red haired sailor who serves as a diving plane operator. • Lutz Schnell as Dufte: The sailor who gets jeered at because of his upcoming marriage, and for a possible false airplane sighting. •
Konrad Becker as Böckstiegel: The
Viennese sailor who is first visited by Hinrich for crab lice. •
Otto Sander as Philipp Thomsen: An alcoholic and
shell-shocked U-boat commander, who is a member of "The Old Guard", when introduced is extremely drunk and briefly mocks Hitler on the stage of the French bordello. (In the "Director's Cut" DVD
audio commentary, Petersen says that Sander was really drunk while they were shooting the scene.) Sometime after
U-96 departs, Thomsen is deployed once again and the two submarines meet randomly in the middle of the
Atlantic Ocean after being put off course by the storm. This upsets the Captain because it means that there is now a gap in the blockade chain. After failing to make contact later, it becomes apparent that Thomsen's boat is missing. When
U-96 intercepts the convoy and sees they are without escorts, the Captain makes the observation that they must be away chasing down another boat; this boat is probably Thomsen's. •
Günter Lamprecht as the Captain of the
Weser: An enthusiastic officer aboard the resupply ship
Weser, he mistakes the 1st Watch Officer for the Captain as they enter the ship's elegant dining room. He pretends to be an ardent Nazi and complains about the frustration of not being able to fight, but boasts about the food that has been prepared for the crew and the ship's "specialities". •
Sky du Mont as an officer aboard the
Weser (uncredited). ==Production==