The Knights of Pythias Building is an historic three-story redbrick Knights of Pythias building located at 315 Main Street in Fort Worth, Texas.

Also known as the Knights of Pythias Castle Hall, it was built in 1901 on the site of an 1881 structure, the first Pythian Castle Hall ever built, which had burned earlier the same year.

The building housed the city's first offset printing press and coin-operated laundry.

In 1981, it was restored and is now part of the Sundance Square area of downtown Fort Worth.

This article about a property in Texas on the National Register of Historic Places is a stub.