A simple method for the radiochemical neutron activation analysis of bromine in rock samples is described. The irradiated samples are ignited in an induction furnace in a flow of air for four minutes. The bromine expelled is collected onto activated charcoal which is measured using a Ge(Li) detector. The yield of the chemical separation is 85–100% and the detection limit is 7 ppb. The method is discussed and results for the analysis of 14 USGS standard rock samples are presented.