Four Saudi crudes were distilled to produce four narrow boiling range naphtha fractions by true boiling point (TBP) distillation method. These fractions were analyzed for paraffins, olefins, naphthenes and aromatics using a multicolumn valve switching gas chromatographic technique in which hydrocarbons were separated and analyzed according to their types and carbon numbers. It was observed that with increasing average boiling points of the fractions, the paraffins decrease while aromatics have an increasing trend.