Using the agar disc diffusion method, the potential antimicrobial activity of edible galangal [Alpinia galanga (Linn.) Swartz.] flower against Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Shigella, and the effects of different drying methods and solvent types on the flowers’ antimicrobial activity were investigated. Oven-dried ethanol (OD Ethanol) extract from galangal flower was the most effective against S. aureus with inhibition zone of about 26–31 mm and the minimum inhibitory concentration (MIC) ranging from 0.352–0.547 mg/mL. No antimicrobial activity was observed on E. coli O157:H7 and Salmonella. Overall antimicrobial activity of oven-dried samples extracted with ethanol (OD Ethanol) was the highest with inhibition zone of 8.94 mm and MIC of 1.457 mg/mL. In contrast, freeze-dried samples extracted with ethanol (FD Ethanol) exhibited the lowest overall antimicrobial activity (7.05 mm and 2.470 mg/mL). This is the first report describing antimicrobial activity of galangal flowers against Grampositive S. aureus.