"The total value of the deals signed today reached 4.9 billion dirhams ($1.34 billion)," Staff Major General Obeid al-Ketbi told reporters.
A contract for maintenance of military aircraft was signed with local firm AMMROC for 1.8 billion dirhams ($490.5 million), Ketbi said.
He said the contracts also included a 430.7 million dirhams ($117.2 million) deal with US manufacturer Raytheon for materials used in GBU12 and GBU58 bombs.
On Monday, Ketbi said the UAE signed a 722 million-dirham ($196-million) contract with US firm General Atomics for the purchase of Predator drones with their complete integrated logistic support systems.
Tuesday's agreements bring the total value of contracts signed so far at the biennial show to $2.76 billion.
Oil-rich UAE invests heavily in defence, just like most other Gulf states that are mainly wary of potential hostilities from neighbouring Iran.