The method of capillary isotachophoresis was used for determination of acesulfame K, saccharin and cyclamates in soft drinks. All samples complied with requirements of Decree of Slovak Republic for acesulfame K and saccharin content. The content of cyclamates was exceeded in some samples above 3.21 mg/l to 114.77 mg/l. Monitoring of time-intensity curves of sweet taste was found that the samples containing the artificial sweeteners had longer progress of sweet taste ceasing and higher maximum intensity. The total duration ranged from 18 s to 36 s in these samples and maximum intensity of sweet taste from 28.3% to 40.5%. In samples containing natural sweeteners the total duration was from 15 s to 21 s and maximum intensity of sweet taste from 20.0% to 36.6 %.