The O'Brien County Courthouse is located in Primghar, Iowa, United States.

It was listed on the National Register of Historic Places in 1981 as a part of the County Courthouses in Iowa Thematic Resource.

[2] Designed by the Des Moines architectural firm of Smith & Loeffer, it is a rather austere version of the Beaux Arts style.

It features six Doric columns in antis on the main facade, and rather large windows.

The interior corridors are made of marble and the handrails in the stairways are finished in bronze.