The deal includes military training, advisory support and exchanges of expertise as Riyadh seeks help against Houthi attacks, officials said.
On Wednesday, Saudi Arabia and Syria signed a defense cooperation agreement, the SPA reported, as Syrian President Ahmed met Saudi Crown Prince Mohammed in Riyadh.
This defense pact occurs as the Iran-aligned Houthi continues missile and drone attacks on Saudi Arabia, prompting the kingdom to seek support from the Middle East and Europe.
Separately, The Saudi Fund signed six agreements with Syria's Finance Ministry on Wednesday, providing over $403 million in loans to support development and service sectors in Syria.
Following the overthrow of Bashar, the kingdom has played a key role in re-establishing Damascus' ties with world powers and continues providing financial assistance to Syria.
Syria was reportedly weighing providing military assistance to Saudi Arabia last month, with diplomats stating any exchange must occur "exclusively through official channels and within the framework of the bilateral agreements.