The printers - used industrially and also on a smaller scale to make digitally designed, three-dimensional objects from plastic - have not been used much for building.
This one used a special mixture of cement, a Dubai government statement said, and reliability tests were done in Britain and China.
"This is the first 3D-printed building in the world, and it's not just a building, it has fully functional offices and staff," the United Arab Emirates Minister of Cabinet Affairs, Mohamed Al Gergawi, said.
"We believe this is just the beginning. The world will change," he said.
The arc-shaped office, built in 17 days and costing about $140,000, will be the temporary headquarters of Dubai Future Foundation - the company behind the project - is in the centre of the city, near the Dubai International Financial Centre.
Gergawi said studies estimated the technique could cut building time by 50-70 percent and labour costs by 50-80 percent. Dubai's strategy was to have 25 percent of the buildings in the emirate printed by 2030, he said.