The bioactive compounds discovered from different plant species have become a gold mine in future therapeutics. The current study focus on authentification of the correct plant species of A. galanga grown in Sri Lanka, determination of antimicrobial, antibiofilm activity, analysis of chemical composition and evaluation of phamacological safety of the crude rhizome extract. The antimirobial activity of the crude galangal hexane extract was tested against six strains of Staphylococcus aureus and four strains of Listeria monocytogens using disk diffusion assay and broth dilution assay.96 well microtitre plate assay was used to test antibiofilm activity against S. aureus 113. The chemical composition of the crude rhizome extract was investigated using Gas Chromatographic and Mass Spectrometric analysis. Pharmacological safety was evaluated using a standard method for acute oral toxicity. All strains of S. aureus tested  showed significantly (p<0.05) higher diameter of inhibition zone ranging from 36 mm to 44 mm including methicillin resistant strain compared to L. monocytogens. The Minimum Inhibitory Concentration and Minimum Bactericidal Concentration of the extract for the six strains tested were found to be 1.25mg/ml and 5mg/ml respectively at 24 hr and did not change after 48 hr except S. aureus MSSA 21D. Crude extract 20 mg/ml showed a significant (p<0.05) lower absorbance (0.299 ± 0.05 nm) at 595 nm in biofilm assay which is 80.68% reduction in biofilm adherence compared to the control. The major chemical compound 1’acetoxychavicol acetate (82.88%) was found to be in highest concentration reported so far. According to the acute oral toxicity study 2000 mg/kg body weight of extract was not toxic to Wistar rats. In conclusion, A. galanga crude extract may be effective as an alternative antibiotic agent to combat antibiotic resistant S. aureus in pharmaceutical industry and as a natural preservative and a disinfectant in food industry to control S. aureus.