Objective To investigate the association of trough concentration (C_min) and peak concentration (C_peak) of vancomycin in steady state with its clinical efficacy and acute kidney injury (AKI). Methods A total of 136 patients who were hospitalized in Changhai Hospital of Naval Medical University (Second Military Medical University) from Nov. 2015 to Apr. 2019 and who received vancomycin therapy (the C_min or C_peak was determined at least once) during hospitalization were retrospectively included. The basic information and related indicators of patients were collected. Both C_min and C_peak of vancomycin were determined for the first time after reaching steady state. According to the C_min, they were divided into <10, 10-15 and >15 mg/L groups; according to the C_peak, they were divided into <25, 25-40 and >40 mg/L groups. The correlations of C_min and C_peak with clinical efficacy and AKI were explored. Results The relationship of C_min with clinical efficacy and AKI was evaluated in 134 cases, with 78, 21 and 35 cases in C_min<10, 10-15 and >15 mg/L groups, respectively. The total effective rate was 76.9% (103/134), and there was no significant difference in the effective rate among all groups (P=0.092). The total incidence of AKI was 15.7% (21/134), and C_min >15 mg/L group had a significantly higher incidence of AKI than <10 mg/L group (34.3%[12/35] vs 6.4%[5/78], P=0.001). The relationship of C_peak with clinical efficacy and AKI was evaluated in 105 cases, with 53, 44 and 8 cases in <25, 25-40 and >40 mg/L groups, respectively. The total effective rate was 79.0% (83/105), and there was no significant difference among all groups (P=0.758). The total incidence of AKI was 16.2% (17/105), and C_peak >40 mg/L group had a significantly higher incidence of AKI than <25 mg/L group (62.5%[5/8]vs 7.5%[4/53], P=0.008). Conclusion There is no significant correlation between blood vancomycin level and clinical efficacy, but the incidence of AKI is higher in patients with high blood vancomycin level.