Created in 1861, Lyon County established its first seat of government in the mining town of Dayton. The economic success of nearby Virginia City prompted officials to invest early in public architecture. Dayton's courthouse was one of the first built in the state.

The county hired Henry Sweetapple as building supervisor. Records indicate that the spending limit for construction was $30,000, but the actual cost is unknown. Completed in 1864, the two-story brick building exhibited an elaborate molded cornice, and brick corner pilasters. Fire destroyed the courthouse in 1909. Daytonites suspected arsonists from Yerington in the south.

Regardless, county commissioners moved the seat of government to Yerington, stopping an effort in Dayton to rebuild their courthouse. In 1911, the county accepted plans from Frederick DeLongchamps for a structure in Yerington, to be located on Main and Grove Streets on land donated by Mary Burton.

The project budget included $35,000 for construction, $3,000 for a jail, and $4,000 for furnishings. It was built by the Ward Brothers and Calder of Reno, and supervised by George W. Hollsworth. During construction, the southern section of the building collapsed and blame was initially directed at DeLongchamps. A formal investigation later exonerated him.

Completed in 1912, the brick structure exhibits a Beaux-Arts design mixed with Neoclassical elements. The exterior includes a highly sculpted cornice with dentils, and granite entrance steps flanked by iron lampposts. Two pairs of terra cotta columns support a large pediment over the front porch. The interior contains a central hall of large white and green tiles, with six-foot-high wainscoting.

Including a recent addition, two structures were added to the rear of the courthouse that match the style of the original building. DeLongchamps designed the first addition in 1935.