Objective To explore sex differences of salivary α-amylase activity (sAA), flow rate, pH value and correlation between sAA activity and flow rate. Methods Saliva samples were collected from 105 healthy volunteers before and after citric acid stimulation. Salivary sAA activity, flow rate and pH value were determined for each samples, and the correlation between sAA activity and flow rate was analyzed. The sex differences of the indices mentioned above were analyzed. Results Citric acid stimulation significantly increased salivary sAA activity, flow rate and pH value, with flow rate undergoing the greatest increase (P <0.01). No significant sex differences in sAA activity, flow rate or pH value were found at baseline, stimulation or acute responses (delta value) to citric acid stimulation. For female subjects, significant positive correlations were found between sAA activity and flow rate in unstimulated and stimulated saliva, between sAA activity delta value and flow rate delta value (P <0.05), and their coefficients kept relatively stable. For male subjects, significantly positive correlation was only found between stimulated sAA activity and flow rate (P <0.01). Conclusion Our study indicates that no sex difference in the sAA activity, flow rate or pH value at basal and acute responses to citric acid stimulation. However, certain sex difference is indicated in correlation between sAA activity and flow rate.