Background: This study was undertaken to investigate and compare the antimicrobial effect of Onion bulbs (Allium cepa) and cinnamon bark (Cinnamomum zeylanicum) against some common bacteria causing Urinary tract infection.Methods: Antimicrobial activity of the plant extract in different concentrations was observed. Commonly isolated bacteria from the urine samples of suspected and untreated patients which were found to be E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa.Results: The comparison between zones of inhibition showed a statistically significant data of both Allium cpea and Cinnamomum zeylanicum. The antimicrobial activity of cinnamon extract showed the maximum effect against Klebsiella pneumoniae, zone of inhibition 25.50 mm±3.72 with 2±l of extract and E. coli with zone of inhibition 11.72mm±1.86. The onion (Allium cepa) extract exhibited some antimicrobial effect, it was most effective against E. coli, though the effect was minimal.Conclusions: From the current study we conclude that the extract of onion and cinnamon bark are promising but were not as effective as the conventional antibiotics such as ciprofloxacin and nitrofurantoin but can be a good alternative in selected group of patient.