FNSS Savunma Sistemleri A.Ş. (English: FNSS Defence Systems A.Ş.) is a Turkish defense manufacturer founded in 1988. It is owned 51% by Nurol Holding of Turkey and 49% by British–American firm BAE Systems Inc., and operates facilities located in Gölbaşı, Ankara.
FNSS was founded as a joint venture between FMC Corporation and Nurol Holding as FMC Nurol Savunma Sanayii A.Ş. It is a major supplier of tracked and wheeled armored vehicles and weapon systems for the Turkish Armed Forces and Allied Armed Forces.