Corn (Zea mays L.) is affected by a number of diseases that lead to yield loss. One of them is brown spot caused by the soil-borne fungus Physoderma maydis. In this study, the bioprotective potential of arbuscular mycorrhizal fungi (AMF) against this disease was carried out in the nursery and field. In a completely randomized block design, two maize varieties namely CMS9015 (V1) and CMS8704 (V2) were used. In the field, two mycorrhizal treatments (V1AMF, V2AMF) and two controls (CV1, CV2) were developed. In the nursery, the treatments consisted of sterilized and mycorrhized soil with disease inoculation (AMF+DI+SS:V1,V2), sterilized soil without mycorrhization with disease inoculation (DI+SS:V1,V2) and non-sterilized soil (NSS:V1,V2).  Disease incidence and severity, plant height and leaf area, root density, root colonization, nitrogen and phosphorus levels were assessed. In the field, the root colonization by the fungus was 63% as compared to 33% for the mycorrhized plants and the controls. Disease incidence and severity were reduced by 33.7% and 35%, respectively, in the mycorrhized plots in the field. The highest levels of phosphorus (0.74 mg g^-1) and nitrogen (9.2 mg g^-1) were obtained in the mycorrhized field treatments. In the nursery, disease incidence and severity were 0% in pots containing sterilized soil with or without mycorrhizal fungi. In the nursery, the phosphorus level of 1.07 mg g^-1 was recorded in the mycorrhizal treatments and the nitrogen level of 7 mg g^-1 was recorded in the leaves of the pots on unsterilized soil. This study provides that AMF can be used for the control of P. maydis in corn.