en Infectious Diseases Infectious Diseases Original Article Original Article Background: Neutropenic patients are vulnerable to a wide spectrum of infectious agents. The aim of this study was to determine the current frequency of bacterial infections in patients with nosocomial fever and neutropenia.<br> Methods: In a retrospective study, the neutropenic patients’ specimens with nosocomial fever were cultured on blood and MacConkey agar plates and evaluated at microbiology laboratory. Ninety-five significant isolates as species level were recognized by bacteriological techniques.<br>Results: The most observed microorganism was Escherichia coli, followed by Pseudomonas aeruginosa, Acinetobacter baumanii, Klebsiella pneumoniae, Coagulase positive staphylococci and Coagulase negative staphylococci. One fungal infection was also observed. Overall, 67% of the organisms were gram negative, 29.8% gram positive, and 3.2% polymicrobial. <br>Conclusion: The changing pattern of infectious agents in neutropenic patients overtime postulates the necessity of other studies to give the most up-to-date insight of the organisms to physicians.<br> Bacterial Infections, Spectrum, Nosocomial, Fever, Neutropenia 698 701 http://caspjim.com/browse.php?a_code=A-10-62-146&slc_lang=en&sid=1 Davood Yadegarynia 1003194753284600813 1003194753284600813 Yes Alireza Fatemi 1003194753284600814 1003194753284600814 No Masih Mahdizadeh 1003194753284600815 1003194753284600815 No Reihaneh Kabiri Movahhed 1003194753284600816 1003194753284600816 No Mohammad Afshin Alizadeh 1003194753284600817 1003194753284600817 No