Peder Nielsen (1 February 1893 – 16 March 1975) was a Danish librarian and entomologist who specialised in the order Diptera especially Nematocera.
[1] Peder Kristian Nielsen was born at Silkeborg, Denmark.
He received training at the Statens Bogsamlingskomité in Copenhagen and in 1917, he became an assistant at Silkeborg library.
Over his more than 40-year career, he came to influence the development in the local library system.
His crane fly (stankelben) collection and other two-wing insects were given to the University of Copenhagen Zoological Museum.