Oscar Werner Tiegs FRS FAA (12 March 1897 – 5 November 1956) was an Australian zoologist whose career spanned the first half of the 20th century. His contribution to the division of the phylum arthropoda into two parts, one including insects, myriapods, and velvet worms, and the other including trilobites, crustaceans, and arachnids, is considered to be an important contribution to zoology. He was acknowledged as having a remarkable ability for apt and beautiful drawings, and as being an excellent microscopist, as having a great capacity for meticulous accuracy, persistent work, and shrewd elicitation of relationships from massive detail. He is considered one of Australia's great zoologists and as having a permanent place in the history of zoology.