ObjectiveTo understand the empiric antimicrobial use in patients with pyelonephritis in a hospital, and provide reference for clinical rational antimicrobial use.  MethodsData of 620 patients with pyelonephritis admitted to the nephrology department of a hospital between January 2011 and September 2014 were collected, application of antimicrobial agents，coincidence between empiric antimicrobial use and antimicrobial  susceptibility testing results in patients with different diseases and different ages were analyzed. ResultsBefore antimicrobial susceptibility testing results were reported, 620 patients use 625 times of antimicrobial agents, 5 of whom used two kinds of antimicrobial agents at the same time, 8 varieties in 15 types of antimicrobial agents were involved, the most frequently used antimicrobial agents were third generation cephalosporins,  cephamycins, and fluoroquinolones. The overall, partial, and non coincidence rate between antimicrobial use and antimicrobial susceptibility testing results were 64.32%(n=402), 8.32%(n=52), and  27.36%(n=171) respectively. The overall coincidence rate in patients with acute pyelonephritis  was higher than those with chronic pyelonephritis (77.61% ［n=357］ vs 58.79%［n=97］，P<0.05). The overall coincidence rate in patients  ＜50 years old and ≥50 years old were 68.12%（156/229）and 75.25%（298/396） respectively，there was no significant different between two groups (χ2=2.93,P=0.09). ConclusionThe noncoincidence rate between empiric antimicrobial use and antimicrobial susceptibility testing results is high, measures needs to be taken to improve the empiric antimicrobials use.