1,4-dioxane is a by product in the production of alcohol ethoxylated surfactants that are widely used in hygienic and cosmetic products. 1,4-dioxane has been considered as possible carcinogen to humans and affect on liver, kidneys and the central nervous system. Because of its effects, the amount of 1,4-dioxane is strictly controlled in hygienic and cosmetic products. So the determination of 1,4-dioxane present in these products is very important. In this study, headspace single drop microextraction-gas chromatography flame ionisation detection was used for quantitative analysis of 1,4-dioxane in surfactant and shampoo. A magnetic stirring bar and 2.0 g of NaCl were introduced in a 20 mL glass vial with a screw cap. After closing the cap, 8.0 mL sample solution was added by a 10.0 mL syringe and the vial was placed on a magnetic stirrer. Sample solution was in equilibrium with it ? s headspace for 10 minutes. Then, needle of a 10.0 ?L GC syringe containing 2.0 µL organic solvent (methyl benzoate) was passed through the silicon septum and the solvent microdrop was exposed to the headspace. After extraction, microdrop was withdrawn into the syringe. The syringe needle was removed from the vial and the sample was injected into the GC. The effective parameters on the method performance such as solvent type, salt addition, drop volume, stirring rate, equilibrium time, extraction time and temperature of sample solution were studied and optimized. The best extraction efficiency was achieved using methyl benzoate as the solvent and 2.0 µL drop volume, 900 rpm stirring rate, 2.0 g NaCl, 10 minutes equilibrium time, 10 minutes extraction time at room temperature. The linear range, limit of detection and relative standard deviation were found 0.5-100 mg L -1 , 0.4 mg L -1 and 7.2% (n=5), respectively. Finally, this method was applied for analysis of real samples such as sodium lauryl ether sulfate, sodium lauryl sulfate, different brand of shampoos, hand washing and dish washing liquids.