The original Cameron County Courthouse, also known as the Rio Grande Masonic Lodge No.

81, is an historic building located at 1131 East Jefferson Street in Brownsville, Texas.

It was designed by architect J. N. Preston in the Second Empire style of architecture.

Built between 1882 and 1883 by S. W. Brooks as the first court house of Cameron County, it served as such until 1914 when the 1912 courthouse was completed.

Its central clock tower and elaborate gabled roof were destroyed in the Labor Day 1933 hurricane and replaced by a flat roof.