Introduction Reduced tongue pressure may render eating and swallowing difficult. The purpose of this study was to investigate whether the tongue training device can also be used as a diagnostic device and whether its sensitivity and specificity are equal to the numerical tongue pressure measuring device. Material and Methods The target group is patients aged 70 years and over who are hospitalised for rehabilitation. Tongue pressure was measured by both, a tongue pressure measuring instrument and a tongue training tool. The diagnosis of the reduced tongue pressure was made with the tongue pressure measuring instrument and set the verified with the novel tongue training tool. Results Sixty‐two participants were included in the study. Forty‐five were classified by the tongue pressure measuring device and 53 by the tongue training device as ‘low tongue pressure’. Spearman correlation confirmed a positive correlation between the tongue pressure measuring device and the tongue training device rs = 0.800, p = 0.01 level (2‐tailed). The tongue training device test identified sensitivity was 100%, and its specificity was 52.9%. The AUC of the ROC curve is 0.901. Conclusion The tongue training device seems a simple, safe and readily available alternative to the tongue pressure measuring device for the diagnosis of low tongue pressure, with an excellent sensitivity and very good specificity.