OBJECTIVE: To explore the correlation between ornidazole (ONZ) salivary concentration and plasma concentrations in healthy subjects, and to provide reference for clinical therapeutic drug monitoring. METHODS: 24 healthy volunteers were selected. After oral administration of ONZ capsules 1.00 g, their venous blood and saliva were collected at 0.25, 0.5, 1.5, 5.5, 10.5, 24.5 and 43.5 h after medication. HPLC method was used to determine the plasma and salivary concentrations of ONZ. The correlation between the two was analyzed. RESULTS: The peak values of plasma and salivary ONZ concentrations appeared immediately at 1.5 h after administration and the peak values were (0.96±0.15) μg/ml and (0.93±0.15) μg/ml; salivary concentration of ONZ was lower than plasma concentration at each time points, but there was no statistical significance (P>0.05); the regression equation of salivary ONZ concentration and plasma concentration was csaliva=1.176 5cplasma-0.199 4(r=0.990 1). The ratio of salivary concentration and plasma concentration of ONZ (S/P) was (0.91±0.06), showing positive correlation (r=0.632-0.970,P<0.05). CONCLUSIONS: The salivary ONZ concentration is significantly correlated with plasma concentration in healthy people, so saliva can be used for therapeutic drug monitoring.