Schloss Johannisberg is a castle and winery in the village of Johannisberg to the west of Wiesbaden, Hesse, in the Rheingau wine-growing region of Germany. It has been making wine for over 900 years. The winery is most noted for its claim to have "discovered" late harvest wine. The palace is a venue of the Rheingau Musik Festival, made available by co-founder Tatiana von Metternich-Winneburg.

Rheingau is one of 13 designated German wine regions (Weinbaugebiete) producing quality wines . It was named after the traditional region of Rheingau, the wine region is situated in the state of Hesse, where it constitutes part of the Rheingau-Taunus-Kreis administrative district. Although, making up only 3 percent of the total German vineyard area, Rheingau has been the source of many historically important innovations in German wine making, and contains many wine producers of international reputation, such as Schloss Johannisberg. Rheingau, with 3,125 hectares of vineyards in 2016, also boasts a higher proportion of Riesling (77.7%) than any other German wine-growing region, with Spätburgunder making up most of the rest (12.2%), followed by Müller-Thurgau.