Rafflesia cantleyi Solms-Laubach is a wild plant found in lowland Peninsular of Malaysia and used widely in traditional medicines. The main objective is to screen antibacterial activity of Rafflesia cantleyi extract. The plant was extracted with cold extraction involving three stages of extraction with solvents such as petroleum ether, ethyl acetate and finally ethanol. All extracts were tested against Staphylococcus aureus ATCC 29523, Staphylococcus epidermidis, Escherichia coli ATCC 25922 and Salmonella typhimurium using well diffusion method. As a result, ethyl acetate and methanol extract showed antibacterial inhibition against tested bacteria whereas petroleum ether failed to show any. Most bacteria are more susceptible to ethyl acetate compared to ethanol extract. The Minimum Inhibitory Concentration (MIC) MICrodilution test and minimum bactericidal concentration (MBC) was carried out on both of the extract. Ethyl acetate extract has MIC ranging between 6.25 – 12.5 mg/ml and MBC between 25.0 – 50.0 mg/ml. Ethanolic extract has much higher MIC and MBC value, which ranges between 25.0mg/ml to 50.0 mg/ml for it’s MIC and has the MBC of 100.0 mg/ml.