The kingdom is hoping the 19 decommissioned pieces of military hardware, submerged at depths up to 28 metres (92 feet), will attract tourists to the already popular diving resort of Aqaba.
The Underwater Military Museum Dive Site includes several tanks, an ambulance, a military crane, a troop carrier, an anti-aircraft battery, guns and a combat helicopter, the Aqaba Special Economic Zone Authority (ASEZA) said.
The sunken items have been "stationed along the coral reefs imitating a battle tactical formation", ASEZA said in a statement.
The museum aims to offer a "new type" of museum experience combining "sports, environment and exhibits" for divers, snorkelers and visitors on glass-bottomed boats, it said.
The launch was marked by a ceremony with music from the Jordanian Armed Forces band and a local folk group, AFP photographers there said.
The northern Red Sea is popular with divers attracted by its coral reefs, which are in relatively good health despite global reef depletion due to global warming.
ASEZA said it had removed "hazardous materials" from the hardware to protect the marine ecosystem.
It said the museum would allow the creation of artificial reefs and promote the recovery of the area's natural reefs by "drawing visitors away to an alternative site."