IN THIS STUDY, A SIMPLE, RAPID AND EFFICIENT METHOD FOR THE EXTRACTION AND DETERMINATION OF GASOLINE IN WATER SAMPLES BY THE HEADSPACE SOLVENT MICRO EXTRACTION (HSME) AND GAS CHROMATOGRAPHY AT SUB (PPM) LEVEL IS DESCRIBED. SOME SIGNIFICANT VARIABLES SUCH AS TYPES OF SOLVENT EXTRACTION AND INTERNAL STANDARD, EXTRACTION TIME, HEADSPACE AND MICRO DROP VOLUMES, TEMPERATURES OF SAMPLE SOLUTION, STIRRING RATE, SALT CONCENTRATION WERE OPTIMIZED. USING OPTIMUM EXTRACTION CONDITIONS (N-HEXADECANAS EXTRACTING SOLVENT, DODECAN INTERNAL STANDARD FOR GASOLINE OCTAN FOR PETROLEUM, EXTRACTION TIME 15 MIN FOR GASOLINE AND 25 MIN FOR PETROLEUM HEADSPACE VOLUME 7 ML FOR GASOLINE AND 6 ML FOR PETROLEUM, MICRO DROP VOLUME 3 ML FOR BOTH, TEMPERATURE OF SAMPLE SOLUTION 30?C FOR GASOLINE AND FOR PETROLEUM 50 ?C, STIRRING RATE 1000 RPM FOR BOTH) A DETECTION LIMIT OF 0.5 PPM FOR GASOLINE AND 1.2 PPM FOR PETROLEUM, A GOOD LINEARITY (R2> 0.9995) IN A CALIBRATION RANGE OF 5- 150 PPM, PRECONCENTRATION FACTOR 150 FOR GASOLINE AND A GOOD LINEARITY (R2> 0.9984) IN A CALIBRATION RANGE OF 10- 150 PPM, PRECONCENTRATION FACTOR 145 FOR PETROLEUM WERE ACHIEVED.