The United States District Court for the Southern District of Ohio (in case citations, S.D. Ohio) is one of two United States district courts in Ohio and includes forty-eight of the state's eighty-eight counties—everything from the Columbus area southward. Appeals from the court are taken to the United States Court of Appeals for the Sixth Circuit at Cincinnati (except for patent claims and claims against the U.S. government under the Tucker Act, which are appealed to the Federal Circuit).

The United States Attorney's Office of the Southern District of Ohio represents the United States in civil and criminal litigation in the court. As of November 2021^[update], the United States attorney is Kenneth L. Parker.^[1]

The court is divided into two divisions.

The United States District Court for the District of Ohio was established on February 19, 1803, by 2 Stat. 201.^[2][3] The act of authorized one judgeship for the court. The district court in Ohio, not being assigned to a judicial circuit, was granted the same jurisdiction as U.S. circuit courts, except in appeals and writs of error, which were the jurisdiction of the Supreme Court.^[3] By the act of February 24, 1807, 2 Stat. 420, the authority of the Ohio district court to exercise the jurisdiction of a U.S. circuit court was repealed, and Ohio was assigned to the newly organized Seventh Circuit. It also provided for a U.S. circuit court for the District of Ohio.^[3] The District was subdivided into Northern and Southern Districts on February 10, 1855, by 10 Stat. 604.^[3] The district judge serving the District of Ohio, Humphrey H. Leavitt, was reassigned to the Southern District of Ohio.

On July 23, 1866, by 14 Stat. 209, Congress reorganized the circuits and assigned Ohio to the Sixth Circuit.^[3] Additional judgeships were created in 1910, 1937, 1966, 1970, 1978, 1984, and 1990.^[3]

As of December 16, 2022^[update]:

Chief judges have administrative responsibilities with respect to their district court. Unlike the Supreme Court, where one justice is specifically nominated to be chief, the office of chief judge rotates among the district court judges. To be chief, a judge must have been in active service on the court for at least one year, be under the age of 65, and have not previously served as chief judge.

A vacancy is filled by the judge highest in seniority among the group of qualified judges. The chief judge serves for a term of seven years, or until age 70, whichever occurs first. The age restrictions are waived if no members of the court would otherwise be qualified for the position.

When the office was created in 1948, the chief judge was the longest-serving judge who had not elected to retire, on what has since 1958 been known as senior status, or declined to serve as chief judge. After August 6, 1959, judges could not become or remain chief after turning 70 years old. The current rules have been in operation since October 1, 1982.

• Courts of Ohio
• List of current United States district judges
• List of United States federal courthouses in Ohio
• United States District Court for the Northern District of Ohio
• United States federal judicial district