Lee Pressman (July 1, 1906 – November 20, 1969) was a labor attorney and earlier a US government functionary, publicly alleged in 1948 to have been a spy for Soviet intelligence during the mid-1930s (as a member of the Ware Group), following his recent departure from Congress of Industrial Organizations (CIO) as a result of its purge of Communist Party members and fellow travelers. From 1936 to 1948, he represented the CIO and member unions in landmark collective bargaining deals with major corporations including General Motors and U.S. Steel. According to journalist Murray Kempton, anti-communists referred to him as "Comrade Big."

Pressman was born Leon Pressman on July 1, 1906, on the Lower East Side of in New York City, first of two sons of immigrants Harry and Clara Pressman of Minsk. His father was a milliner on the Lower East Side of New York City. As a child, Leon survived polio. In his teens, the family moved out to the Bensonhurst section of Brooklyn. In 1922, he entered Washington Square College of New York University, where classmates included Nathan Witt and possibly Charles Kramer (later, fellow AAA and Ware Group members), then transferred to Cornell University, where he studied under labor economist Sumner Slichter.

In 1926, Pressman received his bachelor's degree from Cornell University in Ithaca, New York. In 1929, he received a Juris Doctor degree from Harvard Law School. At Harvard, he was a member of Phi Beta Kappa and was in the same class as Alger Hiss. With future defending lawyer Edward Cochrane McLean, they served on the Harvard Law Review:

Mr. Hiss: ... Lee Pressman was in my class at the Harvard Law School, and we were both on the Harvard Law Review at the same time.

After graduation, he joined the law firm of Chadbourne, Stanchfield & Levy (currently Chadbourne & Parke) in New York City. (During the Great Depression, founder Thomas Chadbourne asserted that the capitalist system itself was "on trial" and became an early champion of both collective bargaining rights and profit sharing for workers.) There, he worked for Jerome Frank (future chair of the SEC). When Jerome left in 1933 to work in FDR's New Deal, Pressman joined a small firm called Liebman, Blumenthal & Levy, to handle Jerome's clients.

In 1933, Pressman joined the Ware Group at the invitation of Harold Ware, a Communist agricultural journalist in Washington, DC: "I was asked to join by a man named Harold Ware" (See "Ware Group" sub-section, below)

In July 1933, Pressman received appointment as assistant general counsel of the Agricultural Adjustment Administration (AAA) by Secretary of Agriculture Henry A. Wallace. He reported to Jerome Frank, who was general counsel. The New Dealers saw the AAA as complementing the National Recovery Act (NRA – where fellow Ware Group member and lifelong Hiss friend Henry Collins worked). As they arrived at AAA, two camps quickly arose: previously existing officials who favored agribusiness interests and New Deal appointees who sought to protect small farmers (and farm laborers) and consumers as much as agribusiness. Or, as Arthur M. Schlesinger, Jr. summarized the attitude, "There were too many Ivy League men, too many intellectuals, too many radicals, too many Jews." By December 1933, Frank had hired John Abt and Arthur (or Howard) Bachrach (brother of Abt's sister Marion Abt Bachrach) to develop litigation strategies for agricultural reform policies.

In February 1935, Chester Davis fired many of Frank's cadre, including Pressman, Frank, Gardner Jackson, and two others.