The spectrum of cerium was recorded in the 300–1240-A region on a 3-m spectrograph with a sliding spark and a triggered spark source. The 5s25p5–(5s25p45d+5s25p66s) transitions of the sixth spectrum of cerium (CE vi) were investigated, and 31 levels of even-parity configurations have been established. Forty-five lines are now classified in this spectrum. Least-squares fitting and Hartree–Fock calculations with relativistic corrections were carried out for satisfactory interpretation of the spectrum.