A solid phase extraction coupled with high performance liquid chromatographic（SPE/HPLC） method was established for the determination of 4 kinds of sodium n alkyl benzene sulfonates in water.The samples were refrigerated and centrifuged，then purified and enriched with MAX complex anion exchange column.Four sodium n alkyl benzene sulfonates were successfully separated by HPLC using acetonitrile-100 mmol/L ammonium acetate（73∶27，by volume） as mobile phase with a flow rate of 1 mL/min，column temperature of 30 ℃，detection wavelength of 225 nm and injection volume of 10 μL.Under the optimal conditions，the calibration curves were linear in the range of 10-50 mg/L for sodium undecylbenzene sulfonte and sodium N tridecylbenzene sulfonate with detection limits of 10 mg/L，and 5-25 mg/L for sodium dodecylbenzene sulphonate and sodium tetradecylbenzene sulfonate with detection limits of 5 mg/L.The spiked recoveries were in the range of 86%-98% with relative standard deviations（RSDs） of 29%-74%.