ABSTRACT A rapid, simple, sensitive, reproducible, and reversed-phase UPLC-MS/MS method was established and validated for determining eltrombopag in human plasma. Eltrombopag was extracted from plasma samples by the protein precipitation technique using acetonitrile. Eltrombopag was separated on a C18- column of Acquity UPLC BEH adjusted at 35°C and mass analysed in a positive electrospray ionization mode. A simple mobile phase of formic acid (0.1%) and acetonitrile in a 25:75 (v/v) ratio was utilized at a flow rate of 400 μL min^-1. The analysis of eltrombopag was carried out within 2 min over a broad range between 50 and 10000 ng mL^-1 (mean r² = 0.9937). Accuracy ranged from 102.70 to 111.43%, whereas the precision (inter- and intra-assay) was not more than 15%. The results confirmed the eltrombopag stability under various conditions. The proposed and validated method was effectively applied to a bioequivalence study of eltrombopag tablet (50 mg) in healthy Egyptian volunteers (n = 31).