An HPLC method for determination of sodium saccharin and acesulfame potassium was newly developed, employing coagulant pretreatment to remove particles dispersed in the sample extract. The method showed recovery of 96-101 for both analytes with a repeatability of less than 1 and a reproducibility of less than 2 . The limit of quantification for sodium saccharin was 0.025 g/kg and that for acesulfame potassium was 0.025 g/kg. Only about 20 min was required for preparation of the test solution, whereas the dialysis method takes much longer.