Walter Karl Johann Roepke (18 September 1882, Hohensalza – 7 February 1961, Wageningen) was a German entomologist who specialised in Lepidoptera and Coleoptera.
He was keen on working in the tropics where he bred and studied the biology of numerous insects.
He suffered from sprue and returned to the Netherlands and from 1919 he was professor at the Agricultural College, Wageningen.
Although working mainly on agricultural pests and diseases he continued to study the lepidoptera of Southeast Asia in his spare time.
[1][2] Roepke was the author of entomological papers on the butterflies of Java and Indomalaya; he described many new taxa.