Sunrise Tower, Office tower in Seebach, Zurich, Switzerland

Sunrise Tower, officially Hochhaus Hagenholzstrasse, stands in the Seebach quarter of northern Zurich. Two towers of 88 and 72.5 metres rise from a shared 25-metre base, with a facade area of 18,000 m². Architect Max Dudler used the same materials and window proportions as at the Diözesanbibliothek Münster, where he also worked.

Construction began in 2000 and was completed in 2005, ending a twenty-year period in which Zurich approved no high-rises. The design came from a competition-winning entry by Wäschle Wüst and Max Dudler's studio. On 25 August 2005, government councillor Hans Hollenstein handed the keys to Sunrise CEO Hans Peter Baumgartner. The owner is the Beamtenversicherungskasse of the Canton of Zurich, which had contractor Zschokke build it for about 200 million francs.

The interior features Scandinavian design elements, including furniture pieces created by Danish designer Arne Jacobsen throughout the building complex.

The structure is easily accessible and visible from multiple vantage points due to its location at a major intersection. The glass and stone exterior can be appreciated from the surrounding streets, making it simple to explore the building's form from different angles.

The building is also known as the diAx Tower, after the mobile provider diAx, its main tenant before the merger into TDC Switzerland. On 11 November 2009, base jumper Ueli Gegenschatz was seriously injured in a jump from the tower during a promotional event and died two days later.