A fast and reliable liquid chromatography coupled with atmospheric pressure chemical ionization tandem mass spectrometry (LC-APCI-MS/MS) method was developed and validated for the quantification of voriconazole in human plasma. The proposed method was validated in a linear range of 50-10,000 ng/ml, and the total run time was 1.5 min. This method was successfully used to support routine therapeutic drug monitoring of voriconazole.