This method is for determining trace amounts of C4 and lower molecular weight alcohols in C3 and C4 olefin/paraffin hydrocarbon streams for the UOP Oleflex or similar processes. Methanol and tert-butanol are reported as a composite. The lower limit of detection is 2 mass-ppm for any alcohol or composite. Aromatics and/or hydrocarbons containing eight or more carbon atoms cannot be present in the stream. If MTBE or ETBE are present in the samples, their reaction products may interfere with the determination of methanol, ethanol and tert- butanol.