X-ray spectra with energies up to 350 keV are reported for two paraboloidal plasma focus devices, the Mark I and Mark III device. Low energy x rays with energies between 5.46 and 29.2 keV were measured with Ross filters. Both time resolved and time integrated spectra were obtained. The higher energy x rays from 60 to 350 keV were measured with K-5 nuclear emulsions. The energies of the individual electrons produced by the photoelectric effect and by Compton scattering in the nuclear emulsion were measured and the x-ray spectra were deduced. The x-ray spectra from each device can be represented by the function (dN/dE)E = AE−m. In the Mark I device, A = (0.85 ± 0.28) × 108 ergs (keV)1.5 and m = (2.5 ± 0.8); in the Mark III device, A = (3.8 ± 1.0) × 108 ergs (keV)1.5 and m = (2.5 ± 1.0), where E is the photon energy in kiloelectron volts. Both spectra are similar in shape, but the x-ray intensity from Mark III, with four times the bank energy, is greater. The x rays appear to be produced by thick target bremsstrahlung on the anode surface by electrons with maximum energies greater than 350 keV and total energy distributions that vary as E−3.3. The start of the x-ray pulse is found to be coincident in time with the current discontinuity in the plasma pinch device.