J. Michael Bishop (born 1936) is an American immunologist and microbiologist who won the 1989 Nobel Prize in Physiology or Medicine.

Bishop was born in Pennsylvania. He attended Gettysburg College as an undergraduate, then earned an MD from Harvard University in 1962.

He began his career working for the National Institute of Allergy and Infectious Diseases, a part of the National Institutes of Health. He then spent a year working for the Heinrich-Pette Institute in Hamburg, Germany before joining the faculty of the University of California, San Francisco. Bishop has remained on the school's faculty since 1968, and has been chancellor of the university since 1998.

Bishop is best known for his Nobel-winning work on retroviral oncogenes. Working with Harold E. Varmus in the 1980s, he discovered the first human oncogene. Their findings allowed the understanding of how malignant tumors are formed from changes to the normal genes of a cell. These changes can be produced by viruses, by radiation, or by exposure to some chemicals.