Cecilienallee 1–2, Architectural heritage monument in Düsseldorf, Germany.

Cecilienallee 1-2 is the neo-baroque palace-like complex built 1907–1911 to plans by Traugott von Saltzwedel as the Royal Prussian Government seat of Düsseldorf. Above a high sandstone base rise four storeys in six wings around three inner courtyards; the 115-metre main facade has a central risalit with six Roman-Ionic half-columns and a copper lantern crowned by a Prussian eagle on a globe.

Built 1907–1911 to plans by Traugott von Saltzwedel, the neo-baroque complex opened on 19 October 1911 as the seat of the Royal Prussian Government of Düsseldorf. Its 1,172 reinforced-concrete piles, driven about 11 m deep by Ed. Züblin & Co. in 69 days, replaced machine halls from the 1902 industrial exhibition. It remains the headquarters of the Düsseldorf regional government.

The building is still the seat of the Düsseldorf regional government, a state intermediate authority of North Rhine-Westphalia. The adjoining Präsidentenschlösschen, once the president's residence, is used for receptions. Inside, the main staircase is modelled on the Escalier des Ambassadeurs at Versailles, and the plenary hall holds wall paintings by Adolf Münzer.

The main facade faces the Rhine along Cecilienallee, opposite today's Rheinpark Golzheim; the Oberlandesgericht stands next door. The building is a working state authority, so visits are limited to the exterior and the entrance area. The copper lantern with the Prussian eagle and the gable inscription "Erbaut unter Wilhelm II. 1907–1911" are best seen from the street side.

The architect was Traugott von Saltzwedel, not Peter Behrens. The main staircase is a copy of the Escalier des Ambassadeurs at Versailles, where Louis XIV received envoys. The copper lantern on the mansard roof carries a Prussian eagle with spread wings on a globe, above an octagonal clock face.