The Museum Wiesbaden is a two-branch museum of art and natural history in the Hessian capital of Wiesbaden, Germany. It is one of the five Hessian State museums, in addition to the museums in Kassel, Darmstadt, Saalburg, and Glauberg.

The foundation of the originally three museums traces back to the citizens of the city and to Johann Wolfgang von Goethe, who stayed in Wiesbaden in 1814/1815. In 1825, he persuaded Frankfurter private collectors Johann Isaac Gerning and Johann Christian Gerning to donate their extensive collections of works of art and antiquities to the Duchy of Nassau in return for the payment of an annuity for life.

Under the responsibility of the newly founded associations, but controlled by the ducal government, the citizens of Wiesbaden and the region were able to quickly expand these collections. Together with the pieces of the Verein für Nassauische Altertumskunde und Geschichtsforschung [de] ("Association for Nassauian Antiquity and Historical Research") founded in 1812, three originally independent museums emerged. In addition to the Verein für Nassauische Altertumskunde und Geschichtsforschung the Nassauischer Verein für Naturkunde [de] ("Nassau Society of Natural Science)" and the Nassauischer Kunstverein [de] ("Nassau Kunstverein") (art society) were responsible for these museums.

Following the death of the Duke, the Hereditary Prince's Palace at Wilhelmstraße, built for his son, was now available for other purposes. In contrast to other cities, at a very early stage, finding rooms for the cultural assets collected by the citizenry was possible. In 1821, the three museums and the regional library of Hessen were thus able to move into the palace, which is now the seat of the Chamber of Commerce and Industry of Wiesbaden. Around the middle of the 19th century, the building became too small, due to the busy collection activities and new acquisitions. The call for a new building became louder and louder. After the three museums came under Prussian control in 1866, the city of Wiesbaden took over these institutions in 1899. This change was generally accepted because Wiesbaden had sufficient funds at the end of the 19th century to promote culture.

According to plans by architect Theodor Fischer, the foundation stone for a new building with three wings was laid at the corner of Wilhelmstraße/Rheinstraße in 1913. Previously, the banker's mansion Mons had stood there, in which the reception building of Ludwigsbahnhof was housed until 1906. The interior design of the three houses was influenced to a large extent by the three directors and the curators, as needs differed.

The first to open was the Gemäldegalerie on 1 October 1915. In the same year, the Natural Sciences Collection was also able to move into the new building, but the Natural Sciences Museum and the Museum of Nassau Antiquities were not reopened until 15 July 1920.

Half of the picture gallery was to be used for changing exhibitions, which were carried out by the Nassauischer Kunstverein in the 1920s and early 1930s. During this time, citizens of Wiesbaden also contributed to important additions to the collections. The natural science collections showed systematic exhibitions on topics of geology, paleontology, and biology. Ecological aspects were also presented for the first time.

During the Second World War, the building was partly used for military purposes. With few exceptions, the collections survived the war unscathed, but the exhibitions were dismantled and most of the showcases were damaged. Only slowly were the rooms able to regain their original function after renovation. This delay had another reason; the Americans, who moved to Wiesbaden after 1945, turned the museum into a Central Collecting Point. Temporarily stored art treasures were shown, such as the bust of Nefertiti or the painting The Man with the Golden Helmet, which was attributed to Rembrandt at the time.