Economically damaging infestations of Hessian fly, Mayetiola destructor Say (Diptera: Cecidomyiidae) have been reported in northern Idaho and damage from the pest has been increasing in this region for the last 12 years. Despite the seriousness of this pest, there is no published information on the natural enemy community associated with Hessian fly in northern Idaho. Studies were conducted in 1998 and 1999 to determine the abundance, distribution, and species composition of Hessian fly parasitoids in northern Idaho. Surveys of commercial wheat fields were conducted in eight counties, and samplings were done in spring wheat trials established near Lewiston, Bonners Ferry, Genesee and Greencreek. Seven species of hymenopterous parasitoids of Hessian fly are reported from Idaho for the first time. Parasitoids were collected from flies in all eight counties. Of the species found, Platygaster hiemalis (Forbes) (Platygastridae) was the most numerous, and Homoporus destructor Say (Pteromalidae) and Pediobius epigonus Walker (Eulophidae) the most widespread. Trichomalopsis subapterus Riley, T. americanus Gahan (Pteromalidae), Eupelmus allynii French and E. vesicularis (Retzius) (Eupelmidae) were encountered in lower numbers and only in one or two counties.