Jean-Jacques Kieffer (1857 in Guinkirchen – 1925 in Bitche) was a French naturalist and entomologist who specialised in the study of parasitic insects. Educated as a priest, Kieffer taught natural science in Bitche, Lorraine while working on the description and classification of insects. His work and publications later became a predominant source of description and classification for entomologists in the early 20th century, in particular with regard to parasitoid wasps, midges, and mosquitos. He collaborated with the English entomologist Peter Cameron.