OBJECTIVE: To optimize the formative excipients for cough remedy granules. METHODS: Effects of different excipients on the formation, moisture absorption and relative critical humidity of cough remedy granules were examined, and the optimal excipients as well as formula were selected by adoption of the comprehensive scoring method. RESULTS: The optimal excipient for preparation of cough remedy granules was lactose, and the best formula comprised of 4 doses of spraying powder and 6 doses of lactose mixture. CONCLUSIONS: The cough remedy granules thus prepared is ideal: good in granularity, easy to dissolve and not liable to moisture absorption.