Bamboo (Bambusa edulis Munro) rhizosphere has been known for its potency to reduce plant pathogen because it contains diverse beneficial microbes, thus bamboo plant itself might be a potential source for bio-control agent discovery. Sclerotium rot, caused by Sclerotium rolfsii Sacc, is one of the most devastating non-specific diseases of plant, including melon (Cucumis melo var. amanta). The aim of this study was to screen and characterise novel bacteria isolates from bamboo powder that have beneficial application for crop protection. Bacillus subtilis BMB26 produced an extracellular metabolite that effective against a wide range of pathogenic fungi, including S. rolfsii, and resistant to heat and protease. Furthermore, to evaluate the application of cell-free filtrates BMB26 on melon plants, a cotyledon test was done under greenhouse condition. A significant decrease was observed in disease incidence (up to 77%) occurred in BMB26-treated melon leaves inoculated with S. rolfsii after 4 days post-inoculation. This result showed that Bacillus subtilis BMB26 has a potential application as a bio-control agent against phytopathogenic fungi.