A large-scale method for producing fungal pathogens for mites, Hirsutella thompsonii and H. nodulosa in two phase culture (liquid and solid), was developed to induce conidiogenesis. The vegetative growth that was obtained in the liquid media of soy meal with shaking, from an inoculum 0.5 g wet weight equivalent to 0.1 g of dry weight, was inoculated on eight solid supports. Generally for most of the strains, the three supports yielding greater conidiogenesis were rice, barley and bran, excluding the strains whose greater sporulation is achieved in rice, oats and sorghum, sorghum and oats as compared to barley and bran, respectively. Maximum production of conidia was obtained with HtM2, HtM4481 and HtC59 strains of H. thompsonii, which reached on solid support 334.75, 269.68 and 137.12 x 10(7) conidia/g, respectively.