Abstract: Objective: To investigate the usage of national essential medicines in a township health center in a border county of
Yunnan Province from 2018 to 2021． Methods: The types, names, dosage forms, sales amounts, and usage of national essential
medicines in the health center from 2018 to 2021 were statistically analyzed, ranked, and the affordability of the top 20 national
essential medicines in sales was evaluated. Results: From 2018 to 2021, the types of national essential medicines used in the health
center and the sales amount increased year by year, and the proportion of the number of national essential medicine varieties to the total
number of medicine varieties in the health center was 67.57%, 72.42%, 73.97%, and 76.63% respectively, while the proportion of sales
amount to the total sales of medicines in the health center was 63.86%, 65.84%, 66.15%, and 70.23% respectively. The affordability of
the top 20 national essential medicines in sales selected was good, and it improved year by year. In terms of rational use of national
essential medicines, the proportion of irrational prescriptions was 17.62%. Conclusion: The implementation of the national essential
medicine system in the health center is relatively good, but there is still a certain gap compared with the requirements of the health
administrative department, and it is necessary to further strengthen the equipment and rational use of national essential medicines.

Key words: medical institutions of border grassroots, national essential medicines, usage, affordability