A comparison study was undertaken to evaluate different analytical methods for measuring boron concentrations in the geothermal fluid from the Los Alamos Hot Dry Rock Geothermal Energy Project and from natural waters collected in the vicinity of the project. Three colorimetric techniques, the carmine method and two azomethine H methods, were compared with two plasma emission spectroscopy methods and with thermal neutron capture-gamma spectroscopy. In general, the analytical results from all the methods were comparable and acceptable; however, each method had its own distinct advantages and disadvantages.