A study was conducted from November 1990 to February 1992 on the prevalence of protozoan infections in the darkling beetle, Alphitobius diaperinus (Coleoptera, Tenebrionidae), from turkey and broiler houses in the southeastern, northeastern, and central Piedmont regions of North Carolina. Darkling beetles were commonly infected with the eugregarine Gregarina alphitobii, an undescribed species of Gregarina (Eugregarinorida, Gregarinidae) and the neogregarine Farinocystis tribolii (Neogregarinorida, Lipotrophidae). Both eugregarine and neogregarine parasites were present throughout the sampling period. A decreasing trend in percentage infection by eugregarines in darkling beetles from broiler houses was observed through time while percentage infection in turkey houses showed a variable trend. Percentage neogregarine infection exhibited a variable trend with a significant difference in the overall rate of infection in the two types of production houses. Neogregarine infection was higher in the broiler houses than in the turkey houses. Both adult and larval stages of the beetle were infected with the gregarines with higher levels of infection observed in the larval stages. Mixed infections with both types of gregarines were highest in the smallest larvae.