Feeding and multiplication of a psocid, Liposcelis bostrychophilusBadonnel, on whole and cracked wheat kernels, a mixture of flour and brewer’s yeast, various kinds of dockage from unclean wheat, and 19 species of seed-borne fungi were determined at 30 ± 0.5°C and 70 ± 5% RH. Dockage consisted of seeds of wild buckwheat, Polygonum convolvulus L.; green foxtail, Setaria viridis (L.) Beauv.; wild mustard, Sinapis arvensis L.; five types of screenings retained on sieves, and dust. Screenings retained by no. 14 (cracked, shriveled wheat and weed seeds); no. 20 (green foxtail and weed seeds); and no. 40 (chaff and hulls) sieves; cracked wheat, Triticum aestivum L. ‘Katepwa’; and wild buckwheat seed were the most favorable for multiplication of this psocid. Dust, whole wheat, green foxtail seed, no. 100 screenings (grain fragments), and Rour with brewer’s yeast sustained growth and development to a lesser degree. Wild mustard seed was a poor food substrate with only marginal survival and egg production. The psocid fed most voraciously on a field fungus, Bipolaris spicifera (Bainier) Subramanian, and least on a storage fungus, Aspergillus niger van Tieghem. Generally, harvest (intermediate) and field fungi including Rhyzopus stolonifer (Ehrenb.) Lind., Nigrospora sphaerica, (Saccardo) Mason, Alternaria alternate (Fr.) Keissler, and Fusarium poae (Peck) Wollenweber were preferred to storage fungi as food substrates; however, Penicillium chrysogenum Thorn supported a high mean population of psocids second only to B. spicifera. Low feeding rates, minimal oviposition, and no multiplication occurred on Penicillium janthinellum Biourge, Fusarium sporotrichioides Sherb., Cochliobolus sativus (Ito & Kurib.) Drechsler ex Dastur, Aspergillus ochraceus Wilhelm, and Aspergillus niger van Tieghem.