As directed by Subdivision M of the Pesticide Assessment Guidelines, the entomogenous fungi being registered for use in the U.S. must be evaluated for nontarget effects on certain beneficial insects. Methods were developed and validated with the cosmopolitan entomogenous fungus Beauveria bassiana (ARSEF252) to evaluate the lethal effects of fungi on the beneficial wasp Trichogramma pretiosum Riley via direct contact. T. pretiosum challenged with B. bassiana (ARSEF252) produce dose responses with LC50's on day three of 10 to the fifth power to 10 to the sixth power and on day four of 10 to the fourth power to 10 to the fifth power conidia/ml. Procedures for conducting the bioassay, maintaining cultures of the insects used, and construction of special tools used in the bioassay are detailed.