Robert Etheridge was born on December 3, 1819, in Ross-on-Wye, Herefordshire, England.

He was an English geologist and paleontologist. After ordinary school education in his native town, he obtained employment in a business house in Bristol. He developed an interest in natural history and attended lectures at the Bristol Philosophical Institution. In 1850, he was appointed curator of its museum and he also became a lecturer on botany at the Bristol medical school. In 1857, he was appointed to a post in the Museum of Practical Geology in London, and eventually became paleontologist to the Geological Survey. In 1865, he assisted Prof. Huxley in the preparation of a “Catalogue of Fossils in the Museum of Practical Geology”. He acquired an exceptional knowledge of British fossils and he ultimately prepared an elaborate work entitled "Fossils of the British Islands, Stratigraphically and Zoologically Arranged". He was elected Fellow of the Royal Society in 1871 and was awarded the Murchison Medal of the Geological Society of London in 1880. He was also president of that Society in 1881-1882. In 1881, Etheridge was transferred from the Geological Survey to the geological department of the British Museum, where he served as assistant keeper until 1891. In 1896, he was the first recipient of the Bolitho Medal of the Royal Geological Society of Cornwall.

In 1845, he married Martha Smith (1815–1884). In 1885, he remarried Helen Hawley (1838–1902) and in 1903, Anna Letitia Pearse (1839–1916). He died on December 18, 1903, in Chelsea, London, England.