The Old Marengo County Courthouse is a historic public building in Linden, Alabama. It was built in 1850 as the third of the six courthouses constructed for the county.

Originally, the first courthouse used by the Marengo County was a one-room log cabin. When the county grew, they built a second one in 1827 which burned down in 1848. The Old Marengo County Courthouse was built immediately as a replacement of the second one, in the same site. It was replaced in 190s, when bigger rooms were deemed needed by the county commissioners. When the offices moved to a new facility, it was used as a public school and then as a church and meeting hall.

The infamous outlaw Reuben Houston ?Rube? Burrow was shot dead in the street in front of the Old Marengo County Courthouse.