The company said the Black Shark advanced torpedo was fired from the submarine Scire in "push out" mode, a water ram expulsion system that ejects the torpedo by means of high water pressure.
The firing was a test to assess progress in development of the torpedo, which will replace A-184 torpedoes now in service with the Italian Navy.
"The Black Shark is the result of Italian research and cutting-edge technology," said Alessandro Franzoni, chief executive officer of WASS, "an example of national excellence in the field of underwater defense equipment through the use of innovative technical solutions for the propulsion systems, power generation and electro-acoustics.
"Thanks to its high quality standards it will succeed in all main international markets."
Whitehead Sistemi Subacquei said the test took place in the Gulf of La Spezia but gave no other details.
Whitehead Sistemi Subacquei is a subsidiary of Finmeccanica and produces underwater systems