Europe's largest aerospace group said the contract, signed with the European Space Agency, was worth around 390 million euros ($488 million).
The contract comes days after European scientists celebrated landing a probe on the surface of a comet for the first time.
NASA intends to use Orion to fly astronauts to an asteroid that has been robotically relocated into a high orbit around the moon. Eventually, the U.S. space agency wants to fly a four-member crew to Mars.
The design of the service module for Orion is based on the Automated Transfer Vehicle (ATV) developed and built by Airbus as a supply craft for the International Space Station.