Mittel U was a class of U-boats built during World War I by the Kaiserliche Marine.

Mittel U U-boats carried 16 torpedoes and had various arrangements of deck guns.

They carried a crew of 39 and had excellent seagoing abilities with a cruising range of around 11,220 miles.

Many arrangements from the Mittel U were also seen on the World War II Type IX U-boats when their design work took place 20 years later.

There were 46 Type Mittel U submarines commissioned into the Kaiserliche Marine.