It said the order was not related to its review of its order for 10 Airbus A380 freighters.
UPS is the sole remaining customer for the freight version of Airbus' delayed superjumbo, after rival FedEx canceled an order for 10. The airline Emirates and aircraft lessor International Lease Finance have converted A380 freighter orders to passenger versions.
An Airbus spokeswoman in France said the 10 A380 orders remained intact. "There is nothing new," she said.
UPS said the wide-body 767s could be used on routes to and from Europe and Latin America as well as on flights within Asia and Europe, and will allow the company to improve its efficiency and speed as it replaces aging aircraft.
The 767, which entered service in 1982, is still one of Boeing's older models. The planes cost between $118 million and $160 million each, but customers usually get hefty discounts on
Boeing took orders for only 10 767s last year. The 787, Boeing's new carbon-fiber, mid-sized widebody plane, took in 157 orders last year.