U-102 was fitted with five  torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one  SK C/35 naval gun, 220 rounds, and one  anti-aircraft gun.
The U-102 had a range of armaments, including five torpedo launchers (four forward and one aft), a single  SK C/35 naval gun with 220 rounds, an anti-aircraft gun, and fourteen torpedoes on board.