Previous research has suggested a possible relationship between stress and the taste threshold. For example, it has been reported that chronic mental fatigue accompanied by dejection, or discomfort, greatly affected the threshold for salt taste. However, there are only a few studies on the effects of acute stress on taste. Therefore, the present study examined the influence of acute mental stress on the threshold for tasting saltiness. Participants in the study were healthy female university students ( N = 57, Mean age: 21.8 ± 0.8 years). They were randomly separated into a stress group and a control group. Then, stress was induced in the stress group by an irregular training experience. Following stress induction, participants sat for 20 minutes and rested. Following this the taste for saltiness was compared in the two groups. All the participants were also assessed for feelings of anxiety and feelings of Pleasantness. Results indicated that the stress group had a significantly higher saltiness score than the control group. In addition, the stress group had less pleasant feeling after stress stimulation, indicating that acute mental stress was successfully induced in the stress group. These results suggest that the threshold for saltiness is reduced under conditions of acute mental stress.