This report describes the analysis of shale oil naphthas and discusses their composition, based on investigation by the Federal Bureau of Mines. Individual compounds identified in this investigation are listed, together with those reported previously in the literature. Also, quantitative data are given on the occurrence of individual compounds and groups of related compounds. A comprehensive analysis is presented for a naphtha from shale oil produced in an N-T-U retort from Green River shale. Results of less detailed analyses are given for 13 other naphthas from Colorado shale oils, for 1 naphtha from Tennessee shale oil, and for 26 naphthas from oils from foreign countries. A description of the general analytical approach used and of techniques developed especially for analyzing shale oil distillates is included.