A rapid and reliable method based on liquid chromatography with UV detection has been developed here to determine the main organic acids in base and sparkling wines of the protected designation of origin Cava. Compounds have been separated by reversedphase mode with a water/acetonitrile solution (95:5 v/v adjusted to pH 2). Figures of merit established at 210 nm are fully compatible with the wine analysis, with correlation coefficients better than 0.996, repeatabilities around 2% and detection limits generally below 1 g L -1 . A total of 53 base wine and 140 cava samples from different coupages have been analyzed. Compositional profiles of organic acids have been used as the source of analytical information for characterization and classification purposes. Results have shown that varietal and blending issues, malolactic fermentation and tartaric acid stabilization affect the composition of organic acids.