Aim. To examine the potential of Pudilan Keyanning toothpaste (PKT) to treat minor aphthous ulcers (MiAU). Method. A double-blind clinical trial was conducted in which 80 volunteers were randomly assigned to the PKT group (N = 40) or the control group (N = 40). The control group used a placebo toothpaste containing no Pudilan extract. At baseline, after 3 days, and after 6 days the following parameters were recorded for the target ulcers: healing rate, healing period, pain (visual analogue scale, VAS), areas of the target ulcerated lesions, degree of exudation, and hyperemia. Results. At the end of the study, the healing rate in the PKT group was 80%, compared to 50% in the control group (p < 0.05). At day 6, the VAS scores, ulcer area, degree of exudation, and hyperemia were significantly different between the two groups, with better performance observed in the PKT group (p < 0.05). Conclusion. PKT toothpaste appears to promote effective healing of MiAU.