Oswald Heer was born on August 31, 1809, in Niederuzwil, Switzerland.

He was a Swiss geologist and naturalist. In 1828, he entered the University of Halle, Germany to study theology but he later switched to natural sciences. In 1834, he became privatdozent in botany at the University of Zürich. He founded and was made a director of the Botanical Gardens there in 1835. In 1840, he advanced to associate professor at Zürich and began his studies in paleobotany. In 1845, he founded and became the president of Zürich's Society of Agriculture and Horticulture. He was also a professor of biology and entomology at the University of Zürich (1852-1883). In 1855, he began to teach taxonomic botany at the Technische Hochschule in Zürich. In 1862, Heer was elected as a member of the American Philosophical Society. In 1873, he received the Wollaston Medal from the Geological Society of London. He was the author of several books, e.g., “Flora tertiaria Helvetiae” in 3 vols. (1855-1859), “Flora fossilis arctica” in 7 vols. (1868-1883), “Flora fossilis Helvetiae” (1876), and “Über die nivale Flora der Schweiz” (1883).

In 1838, he married Margaretha Trümpy (1813–1891). He died on September 27, 1883, in Lausanne, Switzerland.