B Brucea javanica is believed to have anticancer properties in traditional medicine and its ex ct has been show to pos ess antipro_liferativc and pro-apoptotic activities on human carcmo a cells. e aim ofth1s research 1s to analyze the mechanism of Bruceajavanicaextractm poptosis on HSC-2 and HSC-3 cell lines. B. javanica fruit was purchased from West Kuta1, East Borneo and extracted in Mulawarman University. Oral cancer cell lines (HSC-2 and H_SC-3) were routine maintain in DMEM high glucose mediumsupplemented with 10% FBS and 1% penicillin-streptomycin in 5% CO2 and 37° C temperature. There were six different treatment, which is untreated, treated by DMSO, Doxorubicin, and Brucea javanica in different concentration (500 µg/ml, I 00 µg/ml and10 µg/ml) On the next day cells were lysed and the express of cleaved Caspase-3 and cleaved Caspase-9 were analyze with Western Blot. HSC-2 and HSC-3 cell lines which were untreated and treated with DMSO was grown well. The oral cancer cell lines that were treated by Dox.orubicin 10 mM; Brucea javanica 500 µg/ml; Brucea javanica I 00 µg/ml; Brucea javanica 10 µg/ml floating and loss attach with the disk. Brucea java.nica extract exhibited a dosedependent augmentation of apoptosis in all three cell Imes. Western blot or Immunoblot is used to elucidate the specific anticancer mechanisms of the Bruceajavanica extract, cleaved Caspase-3_and cleaved Caspase-9 were expressed. conclusion Brucea javanica induces apoptosis on HSC-2 and HSC-3, more over rt induces intrinsic pathway.