Thomas Wiltshire was born on April 21, 1826, in London, England.

He was a British clergyman, geologist, and paleontologist. He graduated from Trinity College, Cambridge (B.A., 1850; M.A., 1853), was ordained a deacon in 1850 and priest in 1853. During his studies, he developed a life-long interest in geology. In 1856, Wiltshire was elected a Fellow of the Geological Society of London. He served as President of the Geological Association three times (1859, 1862, 1871-1873). In 1863, he was elected Secretary of the Paleontographical Society, an office he held until 1899. From 1874 to 1878, he was one of the Honorary Secretaries of the Geological Society. He acted as Lecturer in Geology (1872-1881) and Assistant Professor (1881-1889) at King's College. In 1890, he was appointed Professor of Geology and Mineralogy at King’s College, a position he held until 1896. In 1888, he became Master of the Clothworkers Company in London. The University of Cambridge conferred upon him an honorary degree of D.Sc. in 1899. He spent several of his summer vacations visiting Yellowstone Park, USA, and the Rocky Mountains in Canada. He donated his collection of minerals to the Mineralogical Museum in Cambridge. Besides being much occupied in scientific pursuits and geological investigations, Rev. Dr. Wiltshire was devoted to clerical work, lecturing, and writing.

In 1850, he married Sarah Harriet Hudson (1826–1905). He died on October 26, 1902, in London, England.