Governor's Mansion, National Register of Historic Places residence in Shawnee, United States.

The Governor's Mansion in Shawnee is a three-story neoclassical house with a footprint of about 60 by 70 feet (18 by 21 m) on a lot of roughly 1 acre (4,000 m2). It has a brick foundation, clapboard siding and a gabled wood shingle roof, with most ceilings 12 feet (3.7 m) high. Ionic columns decorate the east and south sides, and a front bay window carries an open balcony on the first and second stories.

The house was built in 1903 when Shawnee was being considered as a potential capital for the new state of Oklahoma. Although the city did not become the capital, the building remains as evidence of this ambitious chapter in the region's early development.

The mansion shows how wealthy families built their homes in the early 1900s, with design choices that reflected their status and taste. Classical features such as the columns and roof lines were typical of houses that prominent people favored during this era in Oklahoma.

The house stands on a lot of about 1 acre (4,000 m2) in Shawnee's first neighborhood, where the town's early merchants and professionals lived. It is a private residence, so visitors view it from the street; the Ionic columns on the east and south sides and the front bay window with its balcony are visible from outside.

The house is also known as the Giza House, after Zygmund O. Giza, a later owner. Local residents still call it the Governor's Mansion even though no governor ever lived there, and it was listed on the National Register of Historic Places in 1983.