Objective: To observe the clinical efficacy of “Man Yin Yan Ⅰ Formula” on senile vaginitis of kidney-yin deficiency pattern internally and externally. Methods One hundred cases with senile vaginitis were randomized into treatment group and control group, with 50 cases in each group. Treatment group was treated with “Man Yin Yan Ⅰ Formula” and control group was treated with Tinidazole, with the course of 14 days. The clinical efficacy and leucorrhea were observed.  Results: The total effective rate was 98.0% in the treatment group and 88.0% in the control group, and the clinical efficacy of the treatment group was superior to that of the control group (P<0.05). In both groups, scores of the amount, color, smelling of leucorrhea were reduced significantly (P<0.05), and the routine test on leucorrhea was improved markedly (P<0.05). The improvement of symptoms of the treatment group was superior to that of the control group (P<0.05).  Conclusion: “Man Yin Yan Ⅰ Formula” has positive effect on senile vaginitis of kidney-yin deficiency pattern by internal and external use. It is worth to apply in clinic.