Buckeye Partners, formerly known as the Buckeye Pipeline Company, is a distributor of petroleum in the East and Midwest areas of the United States. A direct descendant of Standard Oil, the company is considered one of the largest independent oil pipelines in the United States. Its global headquarters is located in Houston's Greenway Plaza, and it maintains an additional U.S. headquarters in Emmaus, Pennsylvania.

Its predecessor company, the Buckeye Pipe Line Company, was founded in 1886 as part of John D. Rockefeller's Standard Oil. It existed as a subsidiary until it became an independent company after Standard Oil's dissolution in 1911. It changed its name to Buckeye Partners in 1986 during a reorganization that transitioned it into a master limited partnership. The company expanded by buying oil pipelines from mainstream petroleum companies. In 1942, the company purchased Indiana Pipe Line. In 2004, its $517 million acquisition of refined petroleum pipelines and terminals from Shell was approved by the Federal Trade Commission.

Buckeye manages over 6,200 miles (10,000 km) of petroleum pipelines and over 100 truck-loading terminals. Many of its pipelines follow historic Northeastern railroad rights-of-way, and the firm is a surviving fragment of the defunct Penn Central railroad. Among Buckeye's clients were major airports in New York City, leading it to being listed by US federal prosecutors as among the targets of the 2007 John F. Kennedy International Airport attack plot.

In 2019, IFM Investors acquired Buckeye Partners for $10.3 billion in an all-cash deal, paying Buckeye Partners shareholders $41.50 per share. Buckeye Partners is now a wholly-owned subsidiary of IFM under its "Global Infrastructure Fund".