The antimicrobial activity and chemical constituents of the methanolic extract from J. curcas fruit were evaluated in this study. The crude extract was achieved by extraction with 60 % (v/v) methanol. It showed the potencies of antimicrobial activity against P. putida, P. syringae pv. sesami, X. campestris, X. campestris pv. glycines, X. campestris pv. vesicatoria and R. solanacearum with the presence of inhibition zone in the range of 8.0 ± 0.0 to 13.7 ± 0.6 mm and MIC value at 214.29 ± 0.00 µg/mL. Furthermore, flavone compound can be proposed by the analysis of gas chromatographymass spectrometry (GC-MS). According to the group of flavonoid compounds have strong bioactive properties; the results suggested that J. curcas fruit has highly potential as effective natural bioactive sources.