Cumulative 238U(p, f) cross sections are given for 37 nuclides in the energy region 12.5 to 17.5 MeV and for four nuclides up to 30 MeV. Also, 11 independent cross sections are reported. A theoretical model for calculating such quantities is described. The calculated cumulative cross sections are in relatively good agreement with the experimental values, except in the region of symmetric fission, where the calculated values are smaller. The measured total fission cross sections are in good agreement with previous results. From the independent cross sections, the influence of the nuclear shell Z = 50 on the charge distribution of fission fragments can be seen clearly.