A simple, rapid, sensitive and selective LC-MS method was developed and validated for quantification of fexofenadine in human plasma. The LC-MS system was operated under the positive electrospray ionisation mode (ESI). After liquid-liquid extraction, fexofenadine analysis was performed on a C-18 column with a mobile phase of acetonitrile: 10 mM ammonium acetate: formic acid, 70:30:0.1 (v/v/v) at a flow rate of 1 mL min(-1) by using loratacline as internal standard. The lower limit of quantitation was 3 ng mL(-1) for fexofenadine. The assay precision ranged between 1.05 and 12.56% and accuracy ranged between 82.00 and 109.07%. The validated method was successfully used to analyze human plasma samples in bioequivalence studies.