A rapid, precise method for the determination of uranium in nitric acid solution is presented. The uranium in solution is excited by a primary x-ray beam from a molybdenum tube. The intensity of the uranium La, emission line is measured by means of a crystal spectrometer employing a scintillation counter and pulse height analyzer. This intensity is converted to concentration by relating to standard solutions The modification of commercial equipment that simplified the solution analysis are described, as are comparisons of various instrument components.