Howard Temin was born in Philadelphia. His father was an attorney and his mother was involved in educational civic affairs. Temin was interested in biology and during high school, he was accepted into the summer research program at Jackson Memorial Laboratory in Bar Harbor, Maine. Temin spent four summers there learning about the world of biological research.

After high school, Temin went to Swarthmore College and majored in biology. In 1955, he went to graduate school at the California Institute of Technology. Although he started in biology, he became more interested in animal virology. His doctorate thesis was on work done on Rous sarcoma virus in Renato Dulbecco's laboratory. After his Ph.D. in 1959, he stayed in Dulbecco's lab for another year as a postdoctoral fellow. During this time, he developed his provirus theory, which hypothesized that RSV and other RNA viruses entered the cell and then made DNA copies of themselves before integrating into the host genome.

In 1960, he was offered an assistant professorship at the University of Wisconsin-Madison. During the next four years in his basement laboratory, Temin performed the experiments that proved his provirus theory. He published his results in 1964 and in 1975 shared the Nobel Prize in Physiology or Medicine with David Baltimore and Renato Dulbecco for their discoveries concerning the interaction between tumor viruses and the genetic material of the cell.

Temin stayed at the University of Wisconsin-Madison and eventually became a full professor. In 1974 he also became an American Cancer Society Professor of Viral Oncology and Cell Biology. He was also on the editorial boards of several journals: Journal of Virology, Journal of Cellular Physiology, and Proceedings of the National Academy of Sciences.

Temin was a well-recognized figure around the University of Wisconsin-Madison campus. He walked or biked to and from work everyday along the same path following the lakeshore. In 1998, the University dedicated the Howard Temin Lakeshore Path in his honor.

Although Temin did not smoke, he died in 1994 from lung cancer.