Haag am Hausruck is a municipality in the district of Grieskirchen in the Austrian state of Upper Austria.

Starhemberg Castle (Haag am Hausruck) is a Renaissance-style fortress first mentioned in 1246 AD, situated west of the marketplace.

The 16th-century complex, owned by DI Hatschek, served as a military hospital in the early 20th century and a transit camp for refugees in World War II.

Today, it houses the Haager Heimatstuben with exhibits on agriculture, mining, crafts, trade, and castle graphics.

The annual events in Haag am Hausruck include the Kirtag, horse market, Country Festival, Castle Concert, and Beer Wagon Race.