Charles Doolittle Walcott (March 31, 1850 _ February 9, 1927) was an eminent American invertebrate paleontologist. He has become well-known for his discovery in 1909 of well-preserved fossils in the Burgess Shale formation of Canada. In this shale, many very rare, soft-bodied animal fossils have been collected, many by Walcott himself.

In the year following the discovery of 1909, Walcott returned to the area accompanied by his sons Stuart and Sidney. Together they examined all the layers on the ridge above the point where the fossil laden rock had been found, eventually finding the fossiliferous band. Between 1910 and 1924, Walcott returned repeatedly to collect more than 65,000 specimens from what is now known as the Walcott quarry, named after him.

Walcott joined US Geological Survey in 1879 and rose to become its director in 1894. He worked especially on the Cambrian, making numerous field trips and linking the fossils he collected to the sequence of rocks in a way that made important contributions to stratigraphy. He later went on to become Secretary of the Smithsonian Institution after the death of Samuel Pierpont Langley, holding the latter post until his own death. While he held this position, Walcott became one of the most powerful figures in the American scientific community.

Although Walcott spent a considerable amount of time at the Burgess Shale quarry on what became known as Fossil Ridge, he also travelled widely in other areas of the Canadian Rockies. Some of his numerous scientific publications feature spectacular panoramic photographs of the mountains taken from high passes or high on mountain slopes. After his death in 1927, Walcott’s samples, photographs, and notes remained in storage until a new generation of palaeontologists became interested in them in the late 1960’s. Many of his interpretations have been subsequently revised.

Walcott would be little known today if he had been brought to attention by Stephen Jay Gould's book Wonderful Life (1989). In this book, Gould put forth his opinion that Walcott deliberately played down the differences between the Burgess Shale species and the familiar invertebrate forms known from the rest of the fossil record and the present. Many paleontologists would now take a much less negative view of Walcott's descriptions and of the theoretical perspective that shaped them.