【Abstract】Objective To investigate the The guiding significance of blood culture grading report in antimicrobial therapy positive results of bacterial culture. Methods A total of 163 patients with blood stream infections were admitted into hospital from October 2011 to September 2013, 163 patients had definite microbial infection evidence. Serum PCT levels among groups of different pathogens were compared. The analysis of correlation between the PCT concentration of the first assay was got after admission and short-term prognosis was evaluated. The correlation between PCT level and positive results of bacterial culture was also evaluated. Results 163 strains were isolated from the patients. The isolates included Gram-negative bacteria (46.7%), Gram-positive bacteria (49.7%) and fungi(3.6%). Escherichia coli( E. coli), coagulase-negative staphylococcus , staphylococcus aureus, enterococcus and klebsiella pneumoniae were the main pathogen. The proportion of primary blood culture reports issued in 24 h, 48 h, 72 h, 96 h were, respectively 71%, 86%, 94% and 99%; The Primary and secondary reports earlier than the final reports were respectively 42 h and 29 h; Methicillin-resistant Staphylococcus aureus-positive rate was 62.5% ; Extend-spectrum β-lactamases of Escherichia coli and Klebsiella pneumoniae. 95.3% of medication were used before the outcome of blood culture, Antimicrobial adjusted rates related to primary, Secondary and final reports were 36.9 %, 26.1% and 10.6%. With empirical treatment utilization among the top three drugs were Imipenem or meropenem 40.2%, cefoperazone sulbactam 33.1% and ceftriaxone 25.4%. Conclusions With Bloodstream infections, the distribution and spectral characteristics of bacterial resistance were important reference of experience drug-treating .The grading report of blood culture has important guiding value on optimizing antibiotic therapy , Of which the primary report is the most critical step .