Chili (Capsicum annuum L.) is an important spice and one of the major cash crops of Pakistan. Fusarium oxysporum f. sp. capsici (FOC) is a soil-borne ascomycete fungus that causes wilt disease in chili. This study was carried out to assess the seven strains of plant growth-promoting rhizobacteria (PGPR) for their in vitro biocontrol potential against FOC. The PGPR were originally isolated from an allelopathic grass Cenchrus pennisetiformis Steud. These bacteria were used in an in vitro antagonistic assay against FOC. In general, all the seven bacterial species significantly inhibited the growth of fungal pathogen to variable extents. Among these, Bacillus cereus BP-CP3 showed the highest antagonistic potential and inhibited the growth of FOC by 55% followed by B. cereus BP-CP2 and Bacillus subtilus BP-CP5 causing 51% and 41% inhibition.  The best B. cereus   BP-CP3 strain was selected for GC-MS analysis of its secondary metabolites. The metabolites were prepared by incubating the bacterial strain in LB broth for five days. These metabolites were successively fractionated using n-hexane, chloroform and ethyl acetate. These fractions were subjected to GC-MS analysis. Five compounds were identified in n-hexane fraction. Among these, undecane was the most abundant compound followed by dodecane with peak areas of 47.81% and 29.14%, respectively. Likewise, four compounds were identified in chloroform fraction. The major compound in this fraction was hexadecanoic acid, methyl ester with 35.88% peak area followed by 9-octadecenoic acid, methyl ester, (E)- (29.53%). Three compounds were identified in ethyl acetate fraction with hexadecanoic acid, methyl ester (38.05%) as the predominant compound followed by 10-octadecenoic acid, methyl ester (31.98%). This study concludes that B. cereus BP-CP3 is a highly antagonistic strain against FOC.