Robert Baumle Meyner (/ˈmaɪnər/ MY-nur; July 3, 1908 – May 27, 1990) was an American Democratic Party politician and attorney who served as the 44th governor of New Jersey from 1954 to 1962. Before being elected governor, Meyner represented Warren County in the New Jersey Senate from 1948 to 1951.

As governor, Meyner reformed the New Jersey Democratic Party to move away from the domination of the Frank Hague political machine and political corruption scandals of the 1940s and 1950s and restructured state government to centralize and economize its administration. He was broadly popular as governor and is remembered for increasing the efficiency state government without instituting a sales or income tax through increased revenues from existing taxes. Politically liberal, Meyner opposed McCarthyism and criticized President Dwight D. Eisenhower while defending civil liberties and civil rights. In 1960, he unsuccessfully ran for the Democratic nomination for president as a favorite son candidate but finished fifth behind John F. Kennedy.

Robert Baumle Meyner was born on July 3, 1908, in Easton, Pennsylvania, to Gustave Herman Meyner Sr. (1878–1950) and Maria Sophia Bäumle (1881–1968). His father was a German American loom fixer and silk worker from Manchester, New Hampshire. His mother was German, but born in Birsfelden near Basel, Switzerland, to Robert Bäumle from Harpolingen, Baden and to Franziska Oliva Thüring from Istein, Baden. Robert had an older brother, Gustave Herman Meyner Jr. (1907–1996), and a younger sister, Olive F. Meyner Wagner (1913–1982).

In 1916, the Meyner family moved across the state border to Phillipsburg, New Jersey. They briefly moved to Paterson, New Jersey but returned to Phillipsburg by 1922, living on Lincoln Street in a house built by his grandfather. As a young man, Meyner worked various jobs as a newspaper boy, grocery clerk, garage mechanic, and foundry handyman. He was employed as an apprentice coremaker by the Warren Foundry and Pipe Corporation and Ingersoll Rand.

In 1926, Meyner graduated from Phillipsburg High School and entered Lafayette College in Easton, Pennsylvania, where he majored in government and law. He financed his education by working in the silk mills near Easton and Phillipsburg, including as a weaver at the Gunning Silk Company. He was a brother of the Alpha Chi Rho fraternity and in 1928, Meyner formed the Young People's Al Smith for President Club at Lafayette, supporting the unsuccessful Democratic presidential candidate in the 1928 United States presidential election. In his senior year, Meyner was editor in chief of "The Lafayette", a student newspaper.

After graduating from Lafeyette in 1930, Menyer attended Columbia Law School, where he was awarded an LL.B. degree in 1933.

Following his graduation from Columbia, Meyner was employed as a law clerk in Union City and later Jersey City by J. Emil Walscheid and Milton Rosenkranz from February 1933 to April 1936. He was admitted to the New Jersey bar in 1934.

Meyner returned to Phillipsburg in 1936 to take over the practice of a deceased lawyer. He quickly became well-known as a trial lawyer and was admitted to practice before the United States Supreme Court in 1940 and developed a position in favor of judicial reform after "several early traumatic experiences with judges".