A linear and accurate liquid chromatographic tandem mass spectrometric (LC-MS/MS) technique for the quantitation of capmatinib in plasma was developed and subjected for validation. Canagliflogin was employed as an internal standard (IS). Extraction of plasma was executed utilizing 5 mL of ethyl acetate solvent. Analysis was performed Zorbax ODS (50 mm × 2.1 mm x 3 μ) stationary phase at room conditions and a movable solvent composition of 0.1% HCOOH, acetonitrile and methyl alcohol (15:50:35). The flowing rate of the movable phase was 0.4 mL/min. Drug and IS were identified in positive mode of ionization with electrospray mode to get the mass transitions of (m/z): Capmatinib, 413.15/386.14 and canagliflogin (IS), 445.15/267.12. The correlation between capmatinib concentrations and their respective peak proportions to canagliflogin was a straight line over 0.2 to 3200 ng/mL concentration levels. Intra day and inter-day precisions were ≤5.18% for capmatinib. Inter and intra day bias were within the range of −4.17 to 4.53%. The mean measured extraction recovery of capmatinib was 99.23%. Recovery of IS was 98.31%. Capmatinib was subjected for long-term, freeze thaw, bench top, short-term stability, auto-sampler, dry extract, and stock solution stability at low QC and high QC levels and it was stable at all these conditions. The established technique can be utilized to regularly quantitfy of capmatinib in plasma samples in industries, forensic labs, and clinical research organizations.