This paper describes the characterization of Z-pinch xenon plasmas for EUV sources. The plasmas were driven by a 15 J pulsed power generator, which delivers pulsed currents (35 kA, 120 ns) to the short circuit load. We have developed a time-resolved interferogram and a Thomson scattering system to characterize the Z-pinch plasmas. The interferogram using a pulsed Nd:YAG laser (532 nm, 7 ns) shows the temporal development of the radial profile of electron density. The electron density in the core plasma during pinch phase was 1.2 × 1019 cm-3. Preliminary result of the Thomson scattering measurement shows the electron temperature and density at the decay phase of the pinch process were 5.5 eV and 3 × 1017 cm -3, respectively.