Charles Doolittle Walcott was born on March 31, 1850, in New York Mills, New York.

He was a paleontologist. He attended various schools in Utica but never completed his formal education. He took his hobby of collecting fossils and turned it into a lucrative career both commercially and scientifically. After meeting Louis Agassiz of Harvard, who encouraged him to pursue the field of paleontology, he began to work as an assistant to James Hall, the State Geologist of New York. In 1879, he was appointed to the newly formed U.S. Geological Survey and rose to become chief paleologist in 1893 and then director in 1894. He was elected to the National Academy of Sciences in 1896. In 1901, he served as president of the Geological Society of America. In 1907, Walcott left the Geological Survey to become the 4th Secretary of the Smithsonian Institution, a position he held until 1927. In 1921, he was awarded the inaugural Mary Clark Thompson Medal from the National Academy of Sciences. He was a member of the American Association for the Advancement of Science and served as its president in 1923. The Charles Doolittle Walcott Medal is awarded by the National Academy every five years to stimulate work in Precambrian and Cambrian paleontology. The Walcott Peak, where he first discovered the Burgess Shale, a fossil-bearing deposit exposed in the Canadian Rockies on Mount Burgess of British Columbia, a UNESCO World Heritage Site, was named after him.

In 1872, he married Lura Ann Rust (1843–1876), in 1888, he remarried Helena B. Stevens (1858–1911), and in 1914, Mary Morris Vaux (1860–1940), an amateur artist and avid naturalist. He died on February 9, 1927, in Washington, D.C.