The annual contract can be extended for up to five years, the company said, The monetary value of the agreement wasn't disclosed.
AgustaWestland said that under the award it will deliver spare parts, conduct D-level maintenance on the South African air force's fleet of AW109s, repair aircraft components and provide overhaul services.
Technical support services, training and technical publication updates are included as well as an onsite team to conduct the work required.
"This wide ranging support contract will maximize aircraft availability while providing through-life support cost savings to the customer," said Patrick Chabrat, AgustaWestland's head of regional sales.
"The AW109LUH has proven itself to be an ideal multi-role helicopter for the South African air force and this contract will enhance the availability of the aircraft to perform the wide range of tasks it is assigned."
The AW109 LUH is a twin-engine aircraft with a maximum speed of 177 miles per hour, a service ceiling of more than 19,000 feet and a ferry range of nearly 600 miles. Those operated by South Africa feature three 6-inch-by-8-inch flat-screen digital displays.