Having written a letter to the Democratic National Committee, he became a volunteer for the 1964 presidential campaign of Lyndon B. Johnson. His work with the party lead Graves the opportunity to serve as administrative assistant to newly elected Senator Robert F. Kennedy in 1965. Following the assassination of the senator, Graves would land a seat on the advisory board of the Small Business Administration in 1968.
While at Morgan State, Graves made a name for himself as an entrepreneur. Realizing that there was a big market for flowers during Homecoming Week, he went to two competing local florists and cut deals with both to sell flowers on campus. For a percentage of the profits, the florists provided the flowers while Graves covered the campus.
While serving on the SBA's advisory board, Graves' direct work with the agency would lead to his belief for the need of advisement for businesses in economic development and urban affairs convinced Graves to create an annual newsletter that would chronicle issues relevant to black business people and raise awareness of the importance of black consumer power. At the suggestion of then SBA Director Howard J. Samuels, Graves would expand the concept of a newsletter into a full fledged magazine.
Graves started Earl G. Graves, Ltd., and under that holding company, he began the Earl G. Graves Associates management consulting firm. In August 1970, the first issue of Black Enterprise magazine would hit newsstands. Earl G. Graves, Ltd. would grow to include a number of divisions including publishing, marketing, radio, television and event coordinating arms. The firm is the co-owner of the private equity fund Black Enterprise Greenwich Street Corporate Growth Fund, an equity partnership formed with Travelers Group, Inc. The fund aims to invest and promote minority operated businesses.
From 1990 to 1998, Graves served as CEO to Pepsi Cola bottling franchise in Washington D.C. He has held other board and director memberships to a number of corporations including AMR Corporation, Daimler AG, Federated Department Stores and Rohm and Haas, as while as board member of the American Museum of Natural History and Hayden Planetarium in New York City. He is also a member of the Board of Trustees of Howard University.
Graves received the Silver Buffalo Award from the Boy Scouts of America in 1988, and served as the national commissioner from 1990 to 1995. He received the NAACP's Spingarn Medal in 1999. In 2002, Graves was named as one of the 50 most powerful and influential African Americans in corporate America by Fortune magazine.
Graves was appointed by the administration of George W. Bush to serve on the Presidential Commission for the National Museum of African American History and Culture. On April 26, 2007 Earl G. Graves Sr. was inducted into the Junior Achievement U.S. Business Hall of Fame. In 2009, Graves became the recipient of the 2009 NCAA Silver Anniversary Award.
Morgan State University's business school is named after him, Earl G. Graves School of Business and Management.