DHJ can refer to:
Difaâ Hassani El Jadidi, a Moroccan football club Double Holliday Junction, a model of genetic recombination Djahy, the Ancient Egyptian exonym for a subregion of the Middle East Dhinoj, a train station in India; see List of train stations in India#D Dannemora-Harg Railroad, a predecessor of the Upsala-Lenna Jernväg train line in Sweden
See also "D. H. J. Polymath", a pseudonym used by the Polymath Project