U
- Uisko (Finland): 360-ton trawler
- Uller (Norway): 260-ton minelayer
- Uruguay (Argentina): 550-ton sloop
- Uku (Estonia): Gunboat
- Uusimaa (Finland): 400-ton gunboat
Read more about this topic: List Of World War II Ships Of Less Than 1000 Tons
U
Read more about this topic: List Of World War II Ships Of Less Than 1000 Tons