Bernard Leonard (Bernie) Horecker (1914–2010) was an American biochemist known for work on the pentose phosphate pathway, and for cellular regulation in general.

Starting as a biochemist at the United States Public Health Service at the National Institutes of Health, Bethesda, Maryland from 1941 to 1959, Horecker moved to the New York University Grossman School of Medicine, until 1963, then at the Albert Einstein College of Medicine and the Roche Institute of Molecular Biology in Nutley, New Jersey and finally at Cornell University.

[1] Horecker was (with Earl Stadtman) founding editor of Current Topics in Cellular Regulation, a major series in the subject, and continued in the role up to volume 23 (1984).

[1] According to Kresge and colleagues[2] Horecker "made seminal contributions to our understanding of the enzyme-catalyzed reactions in carbohydrate metabolism, especially those of the pentose phosphate pathway."

The breadth of his work can be judged from papers on a wide variety of topics, such as galactose oxidase,[9] metabolic formation of phosphglycerate,[10] protein kinase-C,[11] release of alkaline phosphatase from bacterial cells[12] and prothymosin-α.