OBJECTIVE： To develop a method for concentration determination of voriconazole in human plasma and apply it in the clinic. METHODS： UPLC-MS/MS method was adopted. Using ketoconazole as internal standard， the determination was performed on Shim-pack VP-ODS column with mobile phase consisted of water （containing 1‰ formic acid and 2 mmol/L ammonium acetate）-acetonitrile （gradient elution） at flow rate of 0.3 ml/min and column temperature of 40 ℃.The electrospray ion source， positive ionizing pattern and multiple reaction monitoring were used； the mass transition ion-pairs of voriconazole and internal standard were m/z 351.2→282.2 and m/z 532.1→490.2. RESULTS： The linear range of voriconazole were 1-10 000 ng/ml （r＝0.999 5， n＝5）， and the limit of quantitation was 1 ng/ml； RSDs of inter-day and intra-day were all lower than 10％； method recovery was higher than 90％ （RSD＜8％）， and extraction recovery was higher than 70％ （RSD＜8％）. The plasma concentrations of voriconazole in 10 patients with invasive fungal infection determined by this method were 507.33-7 011.24 ng/ml， and those of 3 patients were outside the recommended treatment concentration range. CONCLUSIONS： The established method is fast， accurate and sensitive， and can be applied for the therapeutic drug monitoring of voriconazole.