The study sought to describe laboratory methods and blood culture procedures and their impact on antimicrobial resistance surveillance among nosocomial bacteria. We conducted a systematic audit of blood culture procedures and practices in the Department of Microbiology, Central Pathology Laboratory at Muhimbili National Hospital, between 19^th and 23^rd March 2012. A total of 25 -30 blood culture specimens were received each day as an indication of low volumes of blood culturing at this site. More blood culture requests came from the neonatal unit of the hospital, and were performed manually with high culture negative specimens. The laboratory performed antibiotic susceptibility testing as per the CLSI guidelines. No vancomycin resistance was ever reported at this site. All blood culture results were entered into the JEEVA laboratory information system, where results could be accessed by clinicians in the wards and data could be retrieved to assess patterns of antimicrobial resistance. Blood culture data entry system lacked quality control checks hence numerous errors and missing data were observed. Our results support the relevance of having improved laboratory procedures and good quality blood culture since surveillance of antimicrobial resistance primarily depends on good laboratory procedures, good quality and reliable blood culture data. This would essentially minimise imprecise estimates of rates of antimicrobial resistance at this hospital.