[1] In 1991, two femora (thighbones), one from an adult and one from a juvenile, were found within a metre of each other at the Dinosaur Cove East site, in the small "Lake Copco" quarry, at the southern tip of Australia.

The type species, Timimus hermani, was formally named and shortly described by Dr Thomas Rich and his wife Patricia Vickers-Rich in 1993/1994.

[2] The holotype specimen, NMV P186303, was found in a layer of the Eumeralla Formation, dating to the Albian faunal stage in the early Cretaceous, some 106 million years ago.

[2] In 1994, Dr. Thomas Rich commented that, while it would have been more ideal to have had the most complete specimen possible as a holotype, it was highly unlikely that future material of Timimus would be found, due to the limited nature of sites to be explored in the area.

However, based on differences between the two femora that were likely unrelated to conspecific allometry or ontogeny, later researchers have suggested that the paratype femur may instead represent an indeterminate maniraptoran.

[8] The habitat of Timimus consisted of polar forests with mild summers but cold and dark winters due to the closer proximity of the area to the South Pole during the Early Cretaceous.

[9] A possible Timimus hermani or related form from the Strzelecki Group near Inverloch, Victoria left a fossil of the first phalanx of its third toe with a depressed fracture on the plantar surface.