The US express companies were the sole industrial buyers of the superfreighter, which Airbus had hoped would break the Boeing 747's dominance of inter-continental airborne cargo.
The cancellation was unexpected as UPS reached an agreement with Airbus last week to delay taking deliveries of its 10 aircraft beyond 2010, while it reviewed its purchases.
But all that changed when EADS and Airbus confirmed a news leak that Airbus would temporarily stop work on the cargo version of the world's largest airliner amid a major restructuring.
"UPS had intended to complete an internal study of whether it could wait until 2012 for the aircraft, but now understands Airbus is diverting employees from the A380 freighter programme to work on the passenger version of the plane," it said.
"Based on our previous discussions, we had felt that 2012 was a reasonable estimate of when Airbus could supply this plane," David Abney, UPS president, said in a statement. "We no longer are confident that Airbus can adhere to that schedule."
Airbus said it respected the decision and remained confident of delivering the first passenger plane in October.
Airbus supporters believe the decision to pull workers off the cargo model was normal given it now has 5 years to develop and deliver the first A380 freighter.
Normal Black, UPS spokesman, said the company would not immediately place an order with another supplier. Boeing is Airbus's only competitor for large aircraft.
The latest bad news ended a dire week for Airbus, which warned on Wednesday that its survival was at stake as it cut jobs and put plants up for sale, triggering a union backlash.