A high-resolution measurement of the neutron-induced fission cross section of 234 U and 237 Np has been performed at the CERN Neutron Time-of-Flight facility. The cross sections have been determined in a wide energy range from 1 eV to 1 GeV using the evaluated 235 U cross section as reference. In these measurements the energy determination for the 234 U resonances could be improved, whereas previous discrepancies for the 237 Np resonances were confirmed. New cross-section data are provided for high neutron energies that go beyond the limits of prior evaluations, obtaining important differences in the case of 237 Np.