The Brewster Old King's Highway Historic District is a historic district encompassing much of Massachusetts Route 6A and portions of some adjacent roads in Brewster, Massachusetts, which was known as the Old King's Highway during colonial times.

The center of Brewster grew around the junction of the Old King's Highway and Harwich Road (now Massachusetts Route 124), with its first church built there in 1700 (the current church is a Greek Revival structure built in 1834), and a nearby burying ground established in 1707.

The civic and commercial functions of the town were spread along the Old King's Highway through the 19th and into the early 20th century.

[2] Prominent landmarks in the district, in addition to the church, include the Old Town Hall, a richly-detailed Queen Anne structure built in 1881; it is located at the junction of the highway with Chatham Street (Massachusetts Route 137).

The current Town Hall was built in 1925, and originally served as a school.