Maggot therapy is an old method used for chronic wound healing before the Penicillin discovery. In literature, maggots of blowflies are successfully employed to clean plenty of chronic necrotic wounds and reduce infecting microorganisms. Therefore this study was conducted to analyze the Calliphora vicina excretions/ secretions and determine their antimicrobial activity against different microorganisms. For this purpose, early third instar Larvae of Calliphora vicina were used to collect excretions/secretions extract. Gas chromatography/ mass spectrometry technique was utilized to analyze and determine the active compounds of the extract. Extract was applied on Bacillus cereus, Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa (P36 & P7) bacteria, and Candida albicans fungus. Analysis of Calliphora vicina excretions/secretions showed the presence of many proteins and fatty acids playing a role as antimicrobial agents against Staphylococcus aureus, Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa (P36 and P7), and Candida albicans, but have no effect against Bacillus cereus.