Explosives, component parts for explosive devices and munitions were found during a house search in Broom Close in Twinbrook on Sunday morning.
The items were examined by army bomb experts and have been removed for forensic examination.
A 57-year-old woman and a man, aged 44, were arrested.
The find was made following a covert surveillance operation against dissident republican terrorists.
They are being questioned by detectives from the PSNI’s Terrorist Investigation Unit at the serious crime suite in Musgrave police station in Belfast.
The man was arrested during a search of a property in the Glen Wood Walk area of Dunmurry on Sunday evening.
A number of items were removed for further forensic examination by officers from the Tactical Support Group.