The Type UB III submarine was a class of U-boat built during World War I by the German Imperial Navy.

[2] German engineers did not miss the chance of expanding the potential of this capable design by incorporating some of its features into a new submersible torpedo boat.

When the convoy system was introduced, it became more difficult to engage enemy merchant shipping without being spotted by destroyer escorts.

[3] Nevertheless, the UB IIIs performed their duties with distinction, sinking 521 ships with a total of 1,123,211 gross register tons (GRT) and 7 warships, including the battleship HMS Britannia, before the end of hostilities.

The resulting design was an improved UB-III that had the benefit of new, all-welded construction techniques and an array of electronic and electromechanical gadgets: the Type VII submarine, the most common U-boat of the Kriegsmarine, was born.