Over the last decade, mushroom production has become one of the most actively developing fields of agriculture in Turkey. About 45% of the total mushroom production and > 50% of the total compost production occurs in the Antalya-Korkuteli district (southwestern Turkey). Major insect pests of mushroom production are cecidomyiid, sciarid and phorid flies with Megaselia halterata (Wood) (Diptera: Phoridae) being the most common species in the-district. In the present study, two commercial microbial products (a bacterial larvicide, Bacillus thuringiensis var. israelensis Berliner (Bti) commercially available as Gnatrol (R) (Valent USA Corp., Walnut Creek, CA), and an entomopathogenic nematode, Steinemema feltiae (Filipjev) Wouts, Mracek, Gerdin & Bedding commercially available as Entonem (R) (Koppert Biological Systems, The Netherlands)] and spinosad, a biologically-derived insecticide that is commercially available as Laser (R) (Dow AgroSciences, Zionsville Road, IN), were evaluated for control of M. halterata in 3 successive mushroom-growing periods. These products were compared with a control treated with water and a conventional chemical insecticide control (chlorpyrifos-ethyl). Treatments were targeted at larvae as soil drenches; treatment efficacy was evaluated by assessing adult emergence and larval damage. Treatments with the microbial products had significantly lower numbers of emerging adults than those observed in water-treated control. There were no significant differences in adult emergence among the 3 microbial products and the chlorpyrifos-ethyl control over the 3 growing periods. Each of the microbial products reduced the incidence of fruit damage by the larvae and resulted in significantly lower damage rates when compared with the water-treated control. These results suggest that these microbial products can be used as alternatives to conventional chemicals in controlling M. halterata on mushroom.