A sensitive and specific liquid chromatography electrospray ionization-mass spectrometry (LC–ESI-MS) is described for quantitation of salbutamol in human urine using nadolol as the internal standard (I.S.). Urine samples were hydrolyzed with -glucuronidase followed by a solid-phase extraction procedure using Bond Elut-Certify cartridges. TheHPLCcolumnwas an Agilent Zorbax SB-C18 column.Amixture of 0.01Mammonium formate buffer (pH 3.5) acetonitrile (85:15, v/v) was used as the mobile phase. Analytes were quantitated using positive electrospray ionization in a quadrupole spectrometer. Selected ion monitoring (SIM) mode was used to monitor m/z 166 for salbutamol and m/z 310 for I.S. Good linearity was obtained in the range of 10.0–2000.0 ng/ml. The limit of quantification was 10.0 ng/ml. The intra- and inter-run precision, calculated from quality control (QC) samples was less than 7.3%. The accuracy as determined from QC samples was within ±2.6%. The method was applied for determining excretion curves of salbutamol.