Introduction: According to the increasing resistance of pathogenic bacteria against antibiotics, searching to find new alternatives to chemical drugs and antibiotics has recently become popular. Therapeutic and pharmaceutical effects of medicinal plants have been considered for decades. The aim of this study was to investigate the effect of alcoholic extract of Geranium plant on the growth of antibiotic resistant bacteria that are prevalent in hospitals.
 
Materials & methods: To investigate the antimicrobial activity of Geranium, clinical and standard strains of Pseudomonas aeruginosa and Escherichia coli bacteria and standard strain of Enterococcus faecalis were treated by 25 and 50 mg/ml concentrations of alcoholic extract of Geranium. For this purpose, disk diffusion method was employed. In order to measure minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), micro broth dilution method was applied.
 
Findings:  The most sensitive bacterium was Pseudomonas aeruginosa due to showing the highest diameter of the inhibition zone (24 mm). The results showed that the alcoholic extract of Geranium plant at a concentration of 50 mg/ml had a higher antimicrobial effect.
 
Discussion & conclusions: The results showed that the alcoholic extract of Geranium plant has anti-bacterial properties. According to being indigenous and having therapeutic effects, further are is recommended to identify the therapeutic effects.