Bipolaris sorokiniana (Sacc.) Shoem. is a notorious fungal pathogen that affects the wheat (Triticum aestivum L.) throughout the world. In this study, antifungal potential of Ocimum basilicum L. extract was investigated against this pathogen under both in vitro and green house conditions. Methanolic extract of O. basilicum showed significance effect and caused 100% inhibition in the mycelial growth of B. sorokiniana in well diffusion method. On the other hand, 100% methanolic extract significantly reduced the disease index by 97% in wheat seedlings by modulating the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities. Furthermore, 100% concentration of methanolic extract also enhanced the dry biomass and 100-grain weight by 17% and 39%, respectively, as compared to control with pathogenic inoculation only.