Cinnamon oil has variety of medical properties against several types of Gram-positive and Gram-negative bacteria, several recent studies deals with the common medical properties of cinnamon oil and its application on infection control and wound management. Methods: This study illustrates new medical properties of cinnamon oil against one of the most virulent pathogens which is an opportunistic organism; P. aeruginosa a Gram-negative pathogens with several virulence factors that we will deal with and how cinnamon oil can overcome its activity. In this study we focus on the virulence activity of P.aeruginosa and how it can be a main reason of chronic wounds infection, inflammation and necrosis. The clinical isolates under investigation in this study are pathogenic isolated from different wounds, ulcers and bed sores from patients of Alexandria university hospitals. These new medical properties of cinnamon oil can hinder the pathogenic properties of P.aeruginosa through facing its virulence factors and thus achieving of complete recovery.